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Discussion Starter #1
On the advice of a senior forum member I'm going to initiate a build page for my 1987 YJ project. I essentially inherited this vehicle from a close friend 17 years after he died of a freak heart attack at the young age of 26. Economics and starting with a different vehicle simply aren't in the cards since this vehicle has sentimental value to a number of people. The vehicle sat in the driveway for 17 years getting minimal maintenance and infrequent use until it became mine in 2014.

I have taken on this project with the intention of turning it into a competent off-roader with acceptable street manners. It will not be a daily driver so I can get kind of stupid with a number of things. Project baseline is an essentially stock 1987 YJ with a 4.2L 6 cyl with Holley 2 BBL carb, and a 2.5" Pro Comp suspension lift.

Project scope, Phase I:
-Fix everything as-is so that it works and is road worthy for the rest of this multi-year build

Project scope, Phase II:
-35" tires
-Suspension and/or flares to accommodate tires
-Re-gear + rear locker
-Replace Dane 35 axle
-Replace BA10 trans
-Rebuild NP231

Project scope, Phase III:
-V8 power-plant
-Air conditioning
-Refine suspension
-Replace or rebuild Dana 30 axle

Base-line vehicle pics below:
 

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Discussion Starter #2
Phase I

Phase I was all about getting this vehicle usable and road-worthy after very little use or maintenance in 17 years, and a lot of abuse before that.

First things were just changing fluids and getting the leaking gas tank seals replaced. That was followed by electrical work on the gauges, lights, etc. Gas tank seals were a lot of work and my gauge has been a problem. The original just simply died so I replaced it with an OEM-style Omix. Well, the Omix was a piece of shit that hadn't been bench tested before leaving the factory. It cooked part of the ancient wiring "board" which is actually a flexible plastic sheet. Fortunately my USAF trained electronics tech neighbor fixed my "board" some ingenious soldering and determined the gauge had WAY too much resistance. Omix sent a replacement which we bench tested BEFORE installing and it was good. Only problem is that my gauge now reads empty at about half of the 20 gallon tank. Not sure if this is the gauge or the sending unit. I have decided this is acceptable for now as the tank will have to be dropped again at some point to install a new rear bumper.

Next significant joy was breaking my engine off of the mounts with some light four wheeling. I suddenly had a heavy thumping from the engine compartment and the shift lever laying across my leg. Turns out one of the legacies my good buddy had left me was the fallout of a front end collision he had had in the mid-90s. A whisky ding no doubt. He T-boned a jersey barrier on the highway late at night and managed to break a couple of the cast iron engine mount bosses off of the engine block. Supposedly the 4.2L/258 has a notoriously weak engine mount which I can confirm. Fortunately the 4.2 has a number of other mount holes cast and threaded into the block on the driver's side, you just need a longer mount to grab them. So, some genius mechanic manufactured a Frankenstein-esque mount that did just that. Unfortunately it's crudeness meant the bolts were largely unsupported so they broke on my during my off road escapade. However, Brown Dog Offroad came to the rescue with exceptionally well designed and well-built mounts that gave me a better than OEM mount despite my broken block bosses. These mounts are NOT cheap however. I think they were $300 or more. It took A LOT of work to prep my block because of course, the broken bolt extractor broke and it took me days to grind it out with a cheapo Dremel-type tool. End result however, is top notch.
 

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Discussion Starter #3
Phase II, part 1

Phase I of my build was essentially complete after replacing the @1994 vintage Bestop Supertop with a Quadratop. Note: after much research I finally decided the Supertop frame was more of a liability than an asset. Replacement Supertops are super expensive and with very limited (and expensive!) options, especially the half doors. Holy crap! I got the Quadratop for less, with the OEM-style frame, so next time I need to replace the top I have many more and cheaper options.

So, Phase I began with the transmission, the much maligned Peugeot BA10/5. Bottom line up front, if you are looking to buy a classic Jeep, a 1987 is probably the single worst year model you could pick. It has a number of unique quirks that make everything a little harder and more expensive. The Peugeot was only in '87s and half of '88s (6 cylinders). If you have a 4 cyl then you have much worse things to concern yourself with than your crappy AX5. Search for a 1987 YJ soft top and you'll see where the problems start, as most catalogs skip from 1986 CJs to 1988 YJs. Still no idea why as the 88 model fit just fine. Anyway, after much research on Novak and Advance Adapter websites, I settles on the venerable AX15 as my best swap.

Despite initial plans to get the new AX15 from Novak, the price after all the rest of the add-ons finally drove me to a remanufactured AX15. I found one for a good price on Ebay from Allstate Gear, which I then found out to my luck is located in my home town. I worked a cash deal in person and they built one to my spec, with the .580 (smaller) pilot bearing, and they had an external slave cylinder bell housing for a really good price. They also provided an AX15 shift tower for a bit more. All told, I was pretty happy despite some teething pains with the shift tower. Don't confuse the AX5 shift tower with the AX15 shift tower.

I got all the other parts from Advance Adapters. I wanted to go with Novak since their website research info is truly awesome, but AA ultimately had a better kit for my purposes which made the price more manageable. So I now have an essentially new AX15 with an external clutch setup. Again, 1987 owners, be wary. 1987 only requires a later model flywheel and starter, which also means fiddling with the 1987-unique solenoid (turned out to be a super simple fix). Just an added bonus of being an elite member of the '87 club.

The AA pilot bearing setup is confusing. I just bought a .580 pilot bearing from a parts store and figured I was done. However, the AA kit comes with a big-ass bronze bushing that does the same thing. I couldn't figure out the AA bushing until I called, but it gets pounded into the end of the crankshaft and negates the need for the pilot bearing (apparently). I am now double-safe with both.

I know what else you're thinking from looking at the pictures.... "what a bad-ass shop this guy has". Well, an added benefit of being a retired veteran is use of the auto shop on base. However, I couldn't leave my Jeep on the lift between pulling the BA10 and installing the rest, so what to do to support the engine with no transmission or transfer case? You'll see my handy 4x4 post solution. A 4x4 slides perfectly over the front leaf springs and under the oil pan. I added some screw-eyes and a tie down strap for added security, and had no problems at all towing my Jeep home.
 

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Discussion Starter #4
Phase II, part 2

So the transfer case isn't really part 2 since it had to be done concurrent with the transmission swap, but it warrants a separate post. Despite the expectation that my 1987 BA10 would be mated to an NP207 transfer case, I lucked out with an NP231 from the factory. Now, as I've said before, this Jeep got some abuse in years past. Mostly it was late night drunken four wheeling to take some non-discriminating local young gal to a remote spot to repeatedly boost her self esteem (It's OK, it was the mid-'90s when that sort of thing was still OK and the hood is made of sturdy steel so no ass-dents).

So while I had the much preferred NP231, this one had a chunk knocked out of the bottom from one of those late night off road forays. An enterprising mechanic recognized that generous smear of epoxy was the only correct way to fix this, and it held up for 20+ years with nary a drip. However, this wasn't good enough for me. I had to replace the BA10-specific 21-spline input shaft with an AX15 friendly 23 spliner. While sourcing parts I came across an Ebay listing from PowertrainPartsPlus for a 6-gear planetary, 1.25" chain, and rear case half to replace my JB Weld special. Price was very good and Duke at PowertrainPartsPlus was super helpful and responsive, and ended up supplying me with the input gear as well.

Additionally, I had decided to install a slip yoke eliminator kit which I sourced from AA, and a Teraflex 2-Low kit. So I had everything needed to make my NP231 super bad ass. Install was a bit involved and took a lot of Youtube videos on reading of instructions, but I got it done.

I couple notes however, usually I would prefer to make one mod at a time in incremental steps to ensure I'm doing it right. That wasn't a viable option with this rebuild. The SYE is pretty much of a known path but the 6-gear planetary and 1.25" chain plus the Teraflex 2-Low kit added unknowns. One disappointment is that the 6-gear planetary comes out of a later model Dodge truck (apparently) which had dispensed with the brass synchronizer ring built into the early YJ NP231s. Elimination of the synchro reduced machining operations (cost) and another part (more cost), but sacrificed shift on the fly and smooth engagement. I can't say I was happy about this. Additionally, I can't say I was super confident in my bench testing of my transfer case as I progressed with the rebuild. Shifting was not all that confidence inspiring as it works better with the unit laying flat rather than standing vertical. Seems to me that it shouldn't matter what orientation it's in.

So everything went together and I was finally satisfied with my bench testing and proceeded with the install. Note: I have no rear drive shaft installed so I am only driving the Jeep in 4WD using the font drive axle (kind of cool as it will easily bake the front tires!). After many delays due to the vacuum actuation of the front axle I was finally able to take an extended test drive. All is fine, EXCEPT, no 4Low. Kind of a problem... Again, no rear drive shaft at the moment, but that shouldn't affect the 4Low function. This will require more testing and conferring with some experts, but I strongly suspect that my 6-gear planetary and 1.25" chain are the culprits. I anticipate having to re-install my factory chain and gear to verify. Will post the results....
 

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Discussion Starter #5 (Edited)
Phase II, part 3

So just a few additional pics of my NP231 additions. I borrowed these pics from another post because I didn't have the forethought to take pics of mine before I installed them, but these are identical to mine.

1. 6 gear planetary vs 3 gear YJ planetary. Note different gear tooth profiles. Make sure they match...

2. YJ narrow vs wide (Dodge?) wide output shaft sprocket. YJ is polished to interface with the synchro. The wide one used no synchro, hence no polish.

3. Wide vs YJ front output sprocket. Not much difference...

4. 1" YJ chain vs 1.25" chain

5. YJ OEM output shaft with OEM sprocket and synchro

So apparently YJs had the synchro because of the front axle vacuum disconnect (CAD). Since the TC had to be shifted into 4WD before the vacuum would get around to actuating the axle lock, the front drive shaft was moving at a different speed than the rear, so the two needed to be synchronized to prevent a huge gear shattering clunk. This is of course for shift on the fly. Later vehicles without the axle disconnect didn't need this as the front and rear driveshafts were already synchronized due to the TC being the only disconnect between them.

So to me the obvious question is, can I source a 1.25" NP231 output shaft sprocket that is synchronized? Rumor is YES, but I haven't found one. Next question is can my existing, non-polished/synchronized 1.25 sprocket be machined polished to be compatible with a synchro? ...and would it be worth the effort and $$$? Who knows, but I miss my synchro... It makes the shifting smoother even when parked and eliminates gear rattle from within the TC. Plus, I guess I just like the bronze...
 

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Discussion Starter #6
Phase II, part 3

So I finally completed my NP231 rebuild after many headaches. I installed it and found that I had no Low gear function. Additionally, my AX15 was leaking fluid around the NP231 input gear. After three complete cycles of removal, rebuilding, and installing the TC only to consistently have no Low gear function, I finally found the culprit, discussed in this link. During my initial NP231 rebuild I neglected to reinstall the input gear retaining ring, which caused the input gear and planetary assembly to drift in and out along the NP231 main shaft. This caused my no Low gear condition and my incorrect assumption that I needed a long input gear. This was incredibly frustrating and I was ready to throw this TC on the scrap pile. Turns out it was my botched assembly that caused both problems.

Prior to this last install cycle I sourced a synchro-friendly drive sprocket from Duke at PowertrainPartsPlus on Ebay and it works like a champ.

I am now satisfied with my NP231 which is rebuilt with a 1.25" chain, 6 gear planetary, TeraFlex 2Low, and an Advance Adapters SYE.

Pic 1, my three drive sprockets, with the 1.25 pro-synchro on the left
Pic 2, my new pro-synchro drive sprocket going onto the AA SYE shaft
Pic 3, my three input gears with spline count on them, long and short
Pic 4 is my previously missing input gear retaining ring that caused so many problems
 

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Discussion Starter #7
Phase II, Ford 8.8 axle assembly install, part 1

After much research I decided on a Ford Explorer 8.8 rear axle assembly. I concluded that is was the best compromise (for me) of strength and cost. I sourced one from a local junkyard for $150 out of a '99 Explorer Sport that had been towed in a few days before. Trying to figure out what was an appropriate donor vehicle required a lot of research, and supposedly a '99 Explorer Sport is NOT an eligible donor for a 31 spline, 59.5" 8.8. Turns out there's a lot of bad info out there. Best way to verify spline count? Go to Autozone.com and look up the replacement axles for the model in question. It tells you exactly what the spline count is.

I power washed the assembly and then removed the perches with a cutoff wheel, pulled the brakes and the axle shafts. Since I'm installing an ARB, and because of my limited access to welding equipment, I opted to have a local drive-line specialist do the re-gear, install the ARB, and set the pinion and weld the perches. I'm glad I did as the re-gearing is best done by a pro in my opinion.

The disc brakes were in good condition although one disc needs to be replaced since it's too worn to salvage. I opened the diff to pull the axles and had a problem with the retaining pin as the long, thin retaining pin bolt had sheared (which is common). However, I was able to remove the remainder with just a metal pick as it was turning freely in the well-oiled threads. I cut off all of the perches with a 4.5" cutoff wheel, then ground them down with a grinding wheel and finished them off with a flap disc.

Pic 1, complete 8.8 fresh out of the Explorer
Pic 2, differential retaining pin and broken bolt
Pic 3, spring perch removal with cutoff wheel
Pic 4, spring perch removed
Pic 5, final spring perch after cleaning it up
 

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Discussion Starter #8
Phase II, Ford 8.8 axle assembly install, part 2

I took my partially disassembled 8.8 to my axle guy who is an experienced mechanic who just recently went on his own after 8 years with the premier local drive-line shop. I saved a far amount of $$ by doing most of the work myself. I brought him the stripped axle assembly and he pulled the gears and carrier, had it sandblasted, then replaced the bearings,and installed the ARB and 4.88 gears. I then did a temporary "dry" axle assembly install so he could set the pinion angle and tack on the perches. By ""dry" I mean un-welded; I filled it with gear oil and installed a Lube-locker gasket with the factory diff cover so he wouldn't get paint on my ARB cover. I then pulled it again so he could weld it up and paint it. Last thing was to put the ARB diff cover on while I could still put the axle vertically on it's yoke, and then install the axle assembly.

I went with a 1310 yoke on the diff in place of the Ford flange disc on advice of my axle guy. He made the observation that it lengthens a drive-line a bit and he opined that the bolt on yokes are less than ideal.

Pic 1, Ford spring perches after removal
Pic 2, new 4.88 gears and ARB ready to go
Pic 3, 1310 yoke in place of Ford flange disc
Pic 4, 31 spline OEM Ford shaft
Pic 5, Complete 8.8 ready for paint, brake line install, and ARB diff cover
 

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Discussion Starter #9
Phase II, Ford 8.8 axle assembly install, part 3

So I installed my 8.8 with a predictable series of unpredictable issues. Now, in Pic #1 (below), behind my sweet ass ARB cover on my new axle assembly, you see a red TJ. By coincidence, this guy was installing a Currie 44 assembly, and he was having problems with the control arms not fitting. He spent $4500 on his 4.10 ARB Currie to about $2000 for my 8.8. You can imagine he was not really happy to hear about my bargain 8.8...

Install itself was fine but I had/have some issues with The Barnes 4WD perches and U-bolts (more on that later). Turns out the entire OEM Ford brake setup is easily adaptable to the JY. The stock plumbing only needed minor mods. I took the brake lines to my local industrial brake shop and asked about stainless flexible lines. The response was, "Why? Is it a show vehicle? Rubber is stronger." Turns out all the OEM rubber lines were in good shape and I only needed an extension to the frame. They pressure tested and flushed the Ford line and made a 14" extension for about $35 and twenty minutes. Flushing my new brakes was a huge pain and took a ton of fluid, but cleaned out my 30 year old rusty fluid. I'm not sure if I'm satisfied with the rear braking action yet but will work on that later.

Several weeks later I got my Tom Woods custom drive shaft. Install was easy, but the CV rewarded me by thumping on the floor panel. Turns out my TC was too high and needed some adjustment downward. I replaced the Energy Suspension transmission mount I had been using with an OEM YJ type which brought down my drive-line maybe 1/4"; enough to stop the thumping but it's still too close. I also tried to take a slight upward arch out of the skid plate/cross-member by driving my F-250 over it a couple times. It did correct the bow but didn't make any noticeable difference to my drive-shaft clearance. I may try cutting 1/2" of rubber off of the bottom of my transmission mount. Not sure if it will work but these mounts are cheap, and the alternative of using skid plate spacers again turns my stomach.

Bizarrely, the YJ has what appears to be a drive shaft "tunnel" pressed into the floor panels, but it doesn't line up with the output shaft on the stock NP231 transfer case. I know the 8.8 has an offset differential but that isn't causing the driveshaft and the "tunnel" to be out of whack. Maybe the body stampings were designed around an earlier generation of TC with the output a little more towards the driver's side?

Pic 1, new 8.8 installed
Pic 2, "new" disc brakes on my YJ
Pic 3, brake line extension
Pic 4, brake line fitting
Pic 5, drive-shaft clearance
 

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Discussion Starter #10
Phase II, Ford 8.8 axle assembly install, part 4

This page is all about the YJ parking brake. Now, my YJ parking brake has never been worth a shit since I've had it. It would set just fine but would ALWAYS release itself at some random point, usually in about 5-10 minutes, so it couldn't be trusted. This axle install was the right time to unfuck my parking brake. First item of business was to remove the parking brake pedal assembly and diagnose the problem. The parking brake assembly has a "sear" just like in almost all firearms. I suspected it was dull, and was correct.

First I partly disassembled the parking brake pedal assembly by grinding off two of the big rivets that hold it together. I ground off from the "inside" or concave side of the assembly. This allowed me to remove some of the internals of this simple mechanism. 30 year old lube had hardened like wax in the teeth on the pedal arm. Also, the teeth on the pedal arm had worn and become somewhat rounded from wear. Lastly, the sear had deformed on the release face and was also a bit rounded. I cleaned out the dried out lube and re-cut the pedal arm teeth with a triangle file. This is mild steel which explains the wear. I also filed down the sear release face to make it square and sharp. This is hardened steel so I started with a little light grinder work and finished with a file. These parts self-adjust so no need to worry about much precision on the fit. I had planned to replace these big rivets with bolts, but they have a step cut in them so that would complicate the job. Ultimately I welded them back in place, sprayed on some ""paint over rust" type spray paint, injected some lithium grease, and it works like it's supposed to.

Next was the parking brake cables. I had planned to just buy some but I was getting turned off on the price. M.O.R.E. will do that as their stuff is outrageous. ECGS was better but then I found this Link that shows how to do it for under $10. Basically, it's genius. Cut the Ford cable sleeves (PULL THE CABLES OUT FIRST!) with a cutoff wheel to approximate the YJ cable length, add two 3/8" brass hose barbs and a couple Dorman #03339 cable stops and the Ford parking brake cables adapt nicely. Check out the Link and be rewarded. I now have a perfectly functioning parking brake for less than $10 in parts. I doubled up on the cable stops for safety and because they are cheap. The stops require a little mod to get the cable to fit but then they work perfectly.

Pic 1, parking brake pedal assy, "outside"
Pic 2, parking brake pedal assy, "inside", grind 2 rivets in the black painted area
Pic 3, parking brake pedal assy sear
Pic 4, parking brake cables
Pic 5, parking brake cables (upside down for some reason)
 

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Discussion Starter #11
Phase II, Ford 8.8 axle assembly install, part 5

This page is about the Barnes 4WD spring/shock perches and U-bolts, and the M.O.R.E. shock relocation brackets.

So I decided on the M.O.R.E. upper shock mount relocation brackets because my new 8.8 shock perches had moved considerably north of where they were on the Dana 35. The M.O.R.E. mounts move them forwards a few inches, in theory regaining some shock travel. If you are doing an 8.8 swap in a YJ I highly encourage you to check out this webpage Ford Explorer 8.8" Axle Install in a '95 Jeep Wrangler. It's a little dated but it and it's sister pages are a wealth of info. "Obi-Wan" says he had a really hard time drilling the two 1/2" holes into the existing shock perches. I, on the other hand, found this task to be a breeze. They key is sharp, new, pilot bits. Drill a 1/8" pilot hole and then just keep stepping up a few drill sizes at a time. Anyway, install was fine but the mounts don't really gain much back on the lost shock travel. Also, they move the shock angle to close to 45°, which changes shock effectiveness. Ultimately I had to go with a shorter shock even with the re-locators. Also of note is that these brackets move the shock mounts inward a few inches. Since I was welding on new shock perches to my new 8.8 axle this was no problem, but might cause a bind in an OEM axle setup.

Next is the Barnes 4WD spring under spring perches. These came on the recommendation of my axle guy, and I don't like them. They invert the U-bolts so the nuts are above the axle, which is a good idea. However, the first U-bolts they supplied left a huge gap between the spring bottom and the bolt. This is just wrong and is a recipe for either a broken spring or broken bolt down the road. I contacted Barnes and they said those bolts were bent incorrectly. They sent me another set with a tighter bend. This improved the gap but did not eliminate it. Also, 150 foot lbs is what they gave for a recommended torque on the U-bolt nuts. Way wrong. As you can see from the pics, the entire Barnes upper mount is distorted and bent inward at 125 foot lbs. I did the other side at 100 foot lbs and it has a little bend too. Either their torque recommendation is way off or these mounts are a bad design. Seems to me they need a rib between the bolts and the U-bolts need a shim between them and the spring.

No comment from Barnes after I sent them these pics. I get the impression that Barnes just makes stuff but doesn't install any of it. If they did these issues would be obvious.

Pic 1, M.O.R.E. shock relocation bracket and new, shorter shock
Pic 2, first set of Barnes4WD U-bolts (note big gap)
Pic 3, Barnes 4WD U-bolts at @ 125 foot lbs torque, passenger side
Pic 4, second set of Barnes 4WD U-bolts (note reduced but still noticeable gap)
Pic 5, Barnes 4WD U-bolts at @ 100 foot lbs torque, driver side
 

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I hope you not driving this on the street with that setup. The axle is in the wrong way. spring perches should rest on the spring and line up with the location pin in the spring. U-Bolts always go around the axle and not the spring.
 

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Something is definitely not right there. The u bolt only contacting the spring on the very edge is not good. There should be a cast piece there that follows the shape of the bolt so it has proper support and the distorted upper mount is concerning too. I am anxious to hear what Barnes has to say.
 

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I hope you not driving this on the street with that setup. The axle is in the wrong way. spring perches should rest on the spring and line up with the location pin in the spring. U-Bolts always go around the axle and not the spring.
Not always... many factory vehicles come with u-bolts around the spring itself - a good example would would Gen 2 Dodge pickups and many smaller GM's.
 

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@LMNOP686 - I think you're missing the lower spring plate. It's a flat piece of steel with some notches to capture the u-bolt. It prevents it from sliding and also allows the u-bolt to pull closely to the spring since the radius of the u-bolt is no longer try to wrap around a flat spring (rather than trying to dig into the spring itself).



I may have a few spare plates in my parts bin, I can check for you. I also have a set of GM craddles that work great as a u-bolt flip-kit for the F8.8.

And 150 ft-lbs is WAY too high for a u-bolt. Depending on thread side, I use 70-90 ft-lbs or as specified in the FSM.
 

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PC1 has it ...you need that plate under the spring, but with the upper mount bent that way, you're not going to get proper bolt tensions since the nut is sitting angled on the mating surface. I'd either holesaw a piece of 1/4 to the axle tube OD and make a center support piece, cut the upper plates off, straighten then weld back on with the center support added in or get rounded U bolts, drop them over the top and get a bottom plate for that type of deal.
 

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Discussion Starter #18
Phase II, Ford 8.8 axle assembly install, part 5

This page is a continuation of my axle/u-joint post from above and there have been some developments over the last month or so. First, Barnes 4WD contacted me and announced they were sending me a new version of the axle top plates that had bent while I was torquing them to Barnes' torque setting of 150 lbs. The new ones are a significant improvement, but mine are already welded on so it will be some time until I get around to replacing them. PC1P advised that even with a rigid top plate, 150 lbs is way too much torque for those U-bolts (he's an engineer). After receiving a factory manual reference from another user I arrived at 90 ft lbs as the baseline torque setting for the rear U-bolts.

Separately, I realized that after my 8.8 install the ass end of my YJ was riding a little low due to the thicker tube on my spring under setup. Not unexpected but I had not made a plan for this as I figured I wouldn't notice the difference. It was also leaning a little to the driver's side. I'm pretty sure both rear springs had sagged over the years and one a bit more than the other. The Pro Comp 2.5" lift springs on it were close to 25 years old, and the good folks at my local 4Wheel Parts were good enough to replace them on warranty with a new set of 4" lift springs, and without too many questions. After doing a bunch of research on lift shackles to compensate for the low rear I decided that new 4" springs were the best answer, and they turned out to be free.

I was a little freaked out when I pulled out my first spring and put it next to the new one, as the new one looked to be significantly shorter. I thought I had the wrong replacement, but maybe just an optical illusion? I could swear that the new one was 4-6" shorter than the old one. However, I confirmed the part numbers and it was correct. Install was not much of a problem, and it turns out someone installed polyurethane bushings years ago. Considering that these bushings had not seen a spec of lube in decades they were in great shape. For an interesting discussion on the correct lube for polyurethane bushings check out this link. I arrived at this site while researching new greasable spring shackles, which I haven't decided on yet.

Pics 1 & 2: New Barnes 4WD top plate with reinforced tabs
Pic 3: New 4" vs old 2.5" Pro Comp springs
Pic 4: Original Barnes 4WD top plate after torquing to 125 Lbs
Pic 5: 20+ year old polyurethane bushings. Note, no lube!
 

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Discussion Starter #19
Phase II, Ford 8.8 axle assembly install, part 6

So as I noted above in this string, these Barnes 4WD U-bolt reversal mounts have been problematic. They have addressed the top plate issue, but since I don't see myself cutting off the existing ones and welding on the new ones any time soon, I will probably just have a friend cut some 1/4" plates on his CNC for me that I can put on top of these. It's a compromise for now.

The other problem was that no bottom plate was supplied by Barnes to address the poor U-bolt to spring contact which left a huge gap, and the fact that those U-bolts are going to try to walk up the curve of the spring every time it flexes. This is potentially a huge issue and I've addressed it with Barnes in detail. Now, Pc1p came to the rescue and offered up some spring plates he got off of a Dodge or some other vehicle that has a U-bolt-spring interface. They arrived yesterday and I cleaned them up with a wire wheel and painted them. They are now sitting famously under my 8.8 on new springs and have perfectly addressed all the remaining issues, so props to Pc1p for the hookup.

I had expected these plates would be cast metal or die-stamped in a 3D die, but these are a super simple 1/8-3/16" strap with a couple of pressed in grooves. I will pass on the recommendation to Barnes that they duplicate these as it can be done with just a hydraulic brake and doesn't need a fancy die.
 

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