Jeep Wrangler Forum

Jeep Wrangler Forum (http://www.wranglerforum.com/)
-   TJ General Discussion Forum (http://www.wranglerforum.com/f282/)
-   -   Thinking about re-gearing (http://www.wranglerforum.com/f282/thinking-about-re-gearing-55358.html)

houstonwrangler 07-14-2010 07:46 PM

Thinking about re-gearing
 
I have a 97' TJ 4.0L. Putting a 3 1/2" Rubicon Express Super Flex kit on it with a 1" body lift. Intend to run 35's with a Superchips tuner and cold air intake. I am thinking I will probably want to swap out the gears. I have 2 questions:
1. Has anyone done gear swap themselves? I have swapped motors and tranny's in several of my trucks, so I am mechanically inclined. How difficult is the process?
2. Anyone have any idea what ratio I would need to make the Jeep run "normal" (I have a 5 gear manual tranny).

HELP!!!!

03 RUBI 07-14-2010 07:53 PM

Do some research on this forum and you'll find that the majority opinion is against CAI and tuner chips. Some gear swaps take more fine tuning than others concerning backlash. Do it wrong and you can wipe out your new gears in no time.

OBM 07-14-2010 08:45 PM

A gear change isn't that complicated. You need some precision tools though, a digital caliper, a dial indicator with a mag base for the dial indicator and a good torque wrench. These can be had at harbor freight for a decent price, except the tourque wrench. Get your gear sets with overhaul bearing sets which will also include a fist full of shims and a simple manual for setting up the gears, these can be had at a decent price at northridge4x4.com or you can buy your parts localy but Dave at Northridge has good prices and service. As far as the geraing goes I presume that you are running a D30 up front and a D35 rear which limits your options but if you plan to run 35s I reccomend 4:88 ratio, that would good gearing for off road and a decent gearing for highway. Good luck.

InfernoGirl 07-14-2010 08:48 PM

Don't regear a D35 for 35's..... Unless you also plan to do the Super 35 thingy. The D35 isn't really tough enough for 35's, so the time/$ spent regearing won't be well spent.

(at least that's what I've read:))

lancetkenyon 07-14-2010 10:21 PM

4.88s

Gumpy2030 07-14-2010 10:28 PM

I can't speak from experience but the general opinion is that 35's are too much for the D35 unless you run the Super 35. So do a search and think about a possible axle swap if you truly want to run 35's. I put the RE 3.5" on mine a few months ago and decided to stick w/ 33's because of the axle issues. Good luck.

Jerry Bransford 07-15-2010 08:22 AM

X3 on not regearing a Dana 35c low enough to run 35" tires. In fact, I would not run 35" tires on a stock Dana 35c period. To run 35" tires, I would only do so after either upgrading the D35c with a Super 35 kit from Superior Axle or replacing the axle with something much stronger like a Dana 44, Ford 8.8, etc.

And with a shop full of tools, welder, air tools, etc. and 40+ years of doing my own vehicle work and modifications, I won't regear my own axles. Even 4x4 shops usually only have 1-2 guys they'll trust to regear axles. Done incorrectly, new ring & pinion gears will be toast in short order. Few experienced mechanics will tackle that job. It's not impossible but you need to understand it's not just about bolting the gears into place. Its a long tedious setup project where you have to take the gears in & out while setting them up so they are positioned correctly relative to each other. Easy it ain't.

TheTJRod 07-15-2010 11:57 AM

He has a Sahara (according to his jeep profile) ,don't they come stock with the D44 in the rear? As said earlier 4.88s will be the sweet spot. Also like Jerry, I would never try a regear myself as I have read many instructions and seen videos on the subject but I know I am not ever going to do it myself unless trained by pros. There are so many measurements required, and if done wrong could at the most require a new axle. I would rather pay someone to do it right than have to do it twice and replace parts it took with it.

IIx4 07-15-2010 12:17 PM

True Newb here!! I have had some of the same questions about regearing.

My dumb question for the day is....How do I find out what I currently have, D35, D44, etc....?

I have a 2000 TJ sport 4.0L.

InfernoGirl 07-15-2010 01:06 PM

Crawl under and look at it .... if it has a plastic fill plug, and is more or less oval it's a 35, more hexagonal with a metal plug it's a 44. Gears are noted on a metal tag about the 10:00 postition on the rear diff.. The last 3 #s are the gears.

4Jeepn 07-15-2010 01:29 PM

Quote:

Originally Posted by Zybeon (Post 689290)
He has a Sahara (according to his jeep profile) ,don't they come stock with the D44 in the rear? .

nope.

lancetkenyon 07-16-2010 11:30 AM

Quote:

Originally Posted by Zybeon (Post 689290)
He has a Sahara (according to his jeep profile) ,don't they come stock with the D44 in the rear?


Not necessarily. My brother has a Sahara with a stock D35. Yet I have a friend who has the D44 in his Sahara. Luck of the draw.

Jerry Bransford 07-16-2010 11:33 AM

Yep the Dana 44 was just an extra cost optional upgrade for the Sahara just like it was for the Sport. :)

TheTJRod 07-16-2010 12:27 PM

Quote:

Originally Posted by IIx4 (Post 689333)
True Newb here!! I have had some of the same questions about regearing.

My dumb question for the day is....How do I find out what I currently have, D35, D44, etc....?

I have a 2000 TJ sport 4.0L.

Quote:

Originally Posted by InfernoGirl (Post 689403)
Crawl under and look at it .... if it has a plastic fill plug, and is more or less oval it's a 35, more hexagonal with a metal plug it's a 44. Gears are noted on a metal tag about the 10:00 postition on the rear diff.. The last 3 #s are the gears.

Here is a Dana 44 (with a slight oil leak)
http://i574.photobucket.com/albums/s...s/0f119df5.jpg

Here is a fancy chart of axles
http://www.akextreme4x4.com/images/t.../Axle%20ID.jpg

InfernoGirl 07-16-2010 12:44 PM

Thanks! I've been needing to save a pic like that! :)

drivebytruckerz 07-16-2010 12:47 PM

that's a great chart.

TheTJRod 07-16-2010 01:42 PM

Here's a link that has a bunch for you to look at.

Axle Identifications

Here is another link, I like this one better as you get some info on it and a pic that better shows you what the cover shape looks like.

And here is another little chart of axle not stock to jeeps, but are used in axle swaps. Other than the first to. the AMC 20 in old Jeeps's and the Chry 8.25" or cherokees. The 8.8 is a popular upgrade as well as the Ford 9" that is not on here. Go all out and get a Dana 60 front and a 14 bolt rear(GM 10.5")
http://www.akextreme4x4.com/images/t...Axle%20ID2.jpg

OBM 07-17-2010 09:45 PM

Quote:

Originally Posted by Gumpy2030 (Post 688683)
I can't speak from experience but the general opinion is that 35's are too much for the D35 unless you run the Super 35. So do a search and think about a possible axle swap if you truly want to run 35's. I put the RE 3.5" on mine a few months ago and decided to stick w/ 33's because of the axle issues. Good luck.

The OP asked what it would take to re-gear and said that he had some mechanical savy so I told him. Rear ends are simple to set up with new gears it just takes time and knowing a few shortcuts. I agree that a D35 is a whimpy rear end but I know several people that run 35s and hammer on them pretty hard and sure they break axles in fact most of them usually pack around at least a couple sets of spare axles but they go out and run. My self I prefer a kingpin D60 in the front and a corporate 14 bolt in the back and running at least 40" tires but that's just me. :)

Jerry Bransford 07-18-2010 08:35 AM

Quote:

Originally Posted by OBM (Post 691746)
Rear ends are simple to set up with new gears it just takes time and knowing a few shortcuts.

I couldn't disagree more with that statement. Gears are anything but "simple" to set up until you have gained the experience (!) and knowledge to set them up. You can't tell a rank beginner installing new R&P geards is a simple job without doing them a huge disservice.

IIx4 07-19-2010 01:58 AM

Thanks for the info, diagrams and links. Tomorrow I will know :)!

OBM 07-19-2010 10:05 AM

Quote:

Originally Posted by Jerry Bransford (Post 691954)
I couldn't disagree more with that statement. Gears are anything but "simple" to set up until you have gained the experience (!) and knowledge to set them up. You can't tell a rank beginner installing new R&P geards is a simple job without doing them a huge disservice.


At our locall club several of us do gears among other things and we help out the other members by helping with instals, lifts, modifications and even fabrication. We have the person that we are doing this for do as much of the work as they are able and when it is time for the technical work we take them step by step throiugh the process and they learn how to do it themselves and they will come and help on other similar projects and soon are able to do this on their own. I hate to send people to a rearend shop and see them get raped, if a person is a fairly competent mechanic they can learn to be self sufficient and be able to help others in the process. Doing any mechanical of fab work on jeeps or any other vehicle is not rocket science it's the simple ABCs. :)

Jerry Bransford 07-19-2010 10:09 AM

That's a good way to do it but that your club feels it necessary to provide so much guidance through the R&P installation process backs up what I was saying, that regearing is not a "simple" process. :)

TerrorJ2001 07-19-2010 10:21 AM

awesome chart sir, :salute:

IIx4 07-23-2010 08:35 AM

WOO HOO!! Dana 44 in the rear and Dana 30 in front. Thanks again for the chart. NOW... I'm running 33's and currently have 3.73 gears. What would you suggest to regear to?
50/50 on the daily driver vs. Off road.

Thanks

lancetkenyon 07-23-2010 02:41 PM

Personal prefference.......4.56s with 33s and either an auto or 5 spd.

I would assume you have the 4.0 I-6 with a D44 in the rear. If you had a 4 popper, I would have said 4.88s.

Jerry Bransford 07-23-2010 02:52 PM

With his 3-speed automatic, 4.56 would be a pretty low ratio for 33" tires. After converting my previous TJ's 5-speed manual to the 3-speed automatic several years ago (the TJ that was stolen in March), I was left to run my 35" tires with 4.88 gearing which was ideal for the 5-speed but not the 3-speed automatic. For offroading it was great but on the highway, rpms were excessive.

The rpms he'd get with his 3-speed automatic with 4.56 and 33" tires would be similar to what mine were with 4.88 gearing and 35" tires which really were excessive on the highway. My highway cruising speed in that TJ became 55-60 mph (65 on rare occasion to avoid being run over) with trucks passing me on the left.

So while I love low axle gearing and wish I had 5.38 in my replacement Rubicon with 35" tires and its 4-speed automatic instead of its current 4.88, I think he'd be better off with 4.10 for his 33" tires and 3-speed automatic. :)

TerrorJ2001 08-08-2010 11:56 AM

Quote:

Originally Posted by InfernoGirl (Post 689403)
Crawl under and look at it .... if it has a plastic fill plug, and is more or less oval it's a 35, more hexagonal with a metal plug it's a 44. Gears are noted on a metal tag about the 10:00 postition on the rear diff.. The last 3 #s are the gears.


If this is the case then I have a 44 in the front and a 35 in the rear???

Front

http://i34.photobucket.com/albums/d1...00807-1951.jpg

Rear

http://i34.photobucket.com/albums/d1...00807-1947.jpg

BTW, I looked for the markings on the axle or a metal tag, no luck

Jerry Bransford 08-08-2010 12:03 PM

Your front axle is a Dana 30. It fools a lot of people into thinking it's a Dana 44 due to its shape and the steel lubricant hole plug but it's really a Dana 30. Only the Rubicon came with a front Dana 44.

Dave blavos 08-08-2010 12:08 PM

I have 33s and 410'gears. 4.0 auto. Seem to be a very good combo for the street doesn't bog or downshift at all on hills and I live in the mountain state

TheTJRod 08-08-2010 02:37 PM

That metal plug and rubber plug doesn't apply to the front axle. Only Rubicons (03+) have a d44 front.

The d30 is substantially smaller.


All times are GMT -5. The time now is 09:25 AM.