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solman 08-02-2011 05:51 PM

Started my Manual to auto swap
I started tearing apart the parts TJ this week. The parts TJ (owned by a friend) is a 98 wrangler sport with a blown head gasket a horrible knock and a rusted out frame. But the good news is it has a 3 speed auto tranny.
I pulled the tranny out Saturday night. After cleaning it up I took it apart a little and welded the stock breather hole shut and re routed it up top where I could run a breather hose to it. Tonight I Swapped the pedal assembly, shifter assembly, and PCM over to my tj I will probably pull my 5 speed out Wednesday night and If all goes well she will be back on the road by Friday. Then I can pull the front axle out and put the new one in(it will be nice to have matching gear ratios in my front and rear axles again)

I cant wait to get back out to Rausch creek with the 8.8 rear, 4.10 gears, 35s, and the auto tranny. It's going to feel like a different Jeep. I'll try to get some pics up of the progress this week.

NHWRANGLER 08-02-2011 10:24 PM

why auto swap? isnt that the wrong way? :P

solman 08-02-2011 10:30 PM

negative. I like riding the rocks and it is so much easier to do so with an auto. I only drive the jeep about 2 to 3k miles a year but I go wheeling at a local offroad park as often as I can. I have been using a hand throttle for about 6 months but I drove a auto tj a while back and ever since I've been hooked :)

NHWRANGLER 08-02-2011 10:39 PM

hmm. i guess i just have big man syndrome. i love my standard. i take one throttle spring off so it idles between 1200 and 2000 rpm and it crawls itself up most trails. i just stay on the brake and clutch. i also have a hand throttle though.

solman 08-04-2011 05:49 PM

Sorry for the lack of pics I will try to get them up asap.
Last night after work I pulled the ax-15 out of my jeep and got the 32rh in place. Now all that's left is to install the transfer case, hook up the wiring and kick down cable, replace the tranny pan with a new mopar extra capacity pan and extended pickup, put the tummy tuck skid back on, install the driveshafts then I should be ready for a test drive :)

geiman 08-04-2011 06:00 PM

When you're playing in the rocks, the auto is amazing. I never truly wanted one, but once I tried it its hard to go back. But lets not turn this thread into one of those debates....

Can't wait to see the finished product! I'm sure your left leg will thank you the next time we're up at Rausch.

adimw 08-04-2011 06:29 PM

you'll need a peg when your doors are off now for that Harley look! I feel ripped off, can't do it in a RHD. Kinda need that foot for my accelerator. Shame I don't have cruise control.

solman 08-04-2011 06:31 PM


Originally Posted by adimw (Post 1439506)
you'll need a peg when your doors are off now for that Harley look! I feel ripped off, can't do it in a RHD. Kinda need that foot for my accelerator. Shame I don't have cruise control.

You could always install a hand throttle. That's what I had with my 5 speed.

BigGreen98 08-04-2011 06:32 PM

What I would give to swap my auto( rebuilt last month or so ) for a five speed. I do to much highway driving and this three speed auto just kills me!

adimw 08-04-2011 06:36 PM


Originally Posted by solman (Post 1439513)
You could always install a hand throttle. That's what I had with my 5 speed.

I'm not THAT keen to stick my leg out the door... and it rarely gets over 24C here in summer. Its freezing at the moment.. 10C at the moment. Doors well and truly on.

solman 08-04-2011 06:41 PM


Originally Posted by BigGreen98 (Post 1439517)
What I would give to swap my auto( rebuilt last month or so ) for a five speed. I do to much highway driving and this three speed auto just kills me!

I do very little highway driving. And the jeep is not my daily driver, for that I have a wrx:). Im running 35" tires with 4.10 gears. fourth gear in the ax-15 is a 1:1 ratio,the same as 3rd gear in the 3 speed auto and at 70mph in 4th gear im only at 2500rpm so it will still be capable of longer trips.

BigGreen98 08-04-2011 06:50 PM

Not to sure about min but at 70 I'm turning about3200 rpms. I don't like it it kills my gas with my35's plus I'm sure it can't be good for my engine

solman 08-04-2011 06:53 PM

You must have 4.56 or even 4.88 gears

BigGreen98 08-04-2011 07:02 PM

Wish I knew I know they aren't stock. Different axles also. They were in it when I bought it

solman 08-04-2011 07:38 PM

Do you know if you have a locker in the rear or if it is an open diff?
If it is open then all you have to do is jack up the rear end so that one tire is off the ground. Rotate your tire 2 full revolutions. While you are spinning the tire count how many revolutions your drive shaft makes.
The number or revolutions that the drive shaft makes would be your gear ratio ( if you have 4.10s the drive shaft will make just a little over 4 revolutions )

If you have a locker, jack up the rear so that both tires are off the ground and only rotate the tire one revolution. Count the drives shaft revolutions the same as above.

Jerry Bransford 08-04-2011 09:10 PM

Assuming your TJ previously had the 5-speed transmission Solman, you'll need to install an extended output shaft seal into your new 32RH or it will leak ATF like a sieve where the 231 input shaft seats into it. When it was origninally installed against the 5-speed, the 231's input shaft is too short to seal into the 32RH so you need to install that extended output shaft seal onto the 32RH.

Don't bother seeing if it will leak, it WILL leak... and big-time too. You'll also need a different crankshaft position sensor for the automatic's bell housing, the one from the 5-speed won't work.

Here's the output shaft seal you need to install into the 32RH... Automatic Seal Extension | TeraFlex Suspensions

I did my 5-speed to 32RH conversion for rock crawling purposes too and it was as much of a boost to its offroad abilities as adding the f/r lockers, 4.88 gearing, and big-ass tires.

That the automatic allowed my Jeep to suddenly easily climb three particular rock waterfalls without a winch that always required a winch prior to the conversion brought home the fact an automatic's torque converter gives 2-3X greater low-end torque than is available with a manual transmission.

Some just don't get the benefits to an automatic transmission on extreme level trails and never will... and very likely because they simply don't do extreme level trails. I've been driving manual transmissions since the 60's but for rock crawling and other extreme-level trails, give me an automatic any day. :)

adimw 08-04-2011 09:15 PM


solman 08-04-2011 09:29 PM

Jerry, I bought the extended seal from Teraflex per an email I got from you a few months ago. I already installed it in the tranny a couple days ago. As for the CPS I have the entire parts jeep at my house that the tranny came from so I left the cps from the auto attached. Hers a break down of what I took from the parts jeep.

32rh 3 speed tranny
shifter assembly
shift cable
kick down cable
cps sensor
tranny mount plate that bolts to transfer case skid
front driveshaft
tranny cooler lines

purchased parts
teraflex extended rear tranny seal ($30)
mopar performance deep tranny pan kit with extended pickup ($55)
b&m external tranny fluid cooler (plan to bypass stock cooler in the radiator) ($65)
10 quarts of atf+4 tranny fluid ($70)

solman 08-04-2011 09:32 PM

As a side note on the teraflex external rear tranny seal. It turned out that I did not need it (I installed it anyway) because I have a transfer case that came from a 2001 tj that had the nv3550 transmission. For whatever reason the input shaft on that transfer case sticks out just as far as the one that come on the auto tranny equipped TJs. I guess it was just the np231j transfer cases that were mated to ax-15s / ax-5s that had a shorter input shaft.

Jerry Bransford 08-04-2011 09:40 PM

Good to know as opposed to the AX-15's whos input shaft is not long enough, that the NV3550's input shaft is long enough to seal into the 32RH and not leak!

solman 08-06-2011 02:36 PM

Well i'm really close now but I had to take a break to go to a friends birthday party. All that is left is to

put fluid in
hook up t-case linkage
install front driveshaft

On a side note If you are thinking about this swap another part I needed from the donor jeep was the t-case linkage bracket that bolts to the t-case. I'll post a pic once I get them on the computer.

computeruser 08-06-2011 04:12 PM

Sounds like a fun project, and the desire to go auto for rocks does make a fair bit of sense.

That said, if I could ever find someone doing that swap locally, I'd be inclined to buy the parts and swap Auto-Manual on my '02...

cork1958 08-07-2011 09:17 AM

Man, what a perfectly good way to ruin a Jeep!! :(

I know an auto would be better for rock climbing though.

Good luck and have fun!! :)

solman 08-07-2011 10:59 AM

Heres a few pics. I keep forgetting to bring my phone out to the garage so I don't have too many.

This is the parts jeep. Its a 98 sport with a blown 4.0 and a rusted frame. Other than that its in really good shape.

The transfer case skid from the parts jeep was tough to get off. the nutserts were spinning inside the frame.

here is the 32rh 3 speed auto

I dont have any pics of the original vent hole welded shut but here is the new breather set up.

Teraflex extended rear tranny seal

heres the old AX-15 and its worn out clutch

my interior after swapping the shifter assembly over

solman 08-07-2011 11:06 AM

Look there's only 2 pedals down there. Its was a little uncomfortable reaching all the bolts but the pedal assembly is swapped out.

The tranny mount on the 32rh is closer to the front that the ax-15. My Undercoverfabworks ultra high clearance skid already had the holes in the right place I just needed to steal the bracket from the parts jeep transfer case skid.

Here is the 32rh in place with the Mopar performance deep pan and extended pickup kit installed.

the new tranny breather hose sits right above the PCM the was taken from the parts jeep as well.

So far that is where Im at with the swap. I did install the tranny cooler yesterday but I havent taken any pics yet. Tonight I should have her all done and ready for a test drive.

solman 08-07-2011 11:10 AM

One more pic. This is the difference between the front driveshaft from an auto tj and a manual tj. The auto is a smaller diameter so that it will clear the wider auto tranny.

cavediverjc 08-07-2011 11:42 AM

Great progress, solman. You'll definitely love the auto for the rocks. My CJ was a manual and I didn't think it could get any better with an auto, so it was a major mind-f*(k for me to believe it when all my rock-crawler buddies had autos in their Jeeps. They talked me into an auto Jeep since I wanted to play in the rocks and I haven't looked back! Have fun and let us know what you think after your first rock run with the auto!! :thumb:

solman 08-07-2011 11:47 AM

Thanks, and I cant wait to get back on the trail with it.

Jerry Bransford 08-07-2011 02:54 PM

Very nice swap, you are going to love it once you start driving it. Just make sure to get the TC cable adjusted so it is just taut without it actually pulling the throttle lever any.

Congrats on a very nice successful swap! :thumb:

solman 08-07-2011 04:45 PM

Thanks Jerry, and yes the kickdown cable is set right. No slop but not too much tension. Well I buttoned everything up today and took it for a test drive. All I can say is WOW :D I should have done this a while ago. It shifts great it feels like it has way more low end power and it drops into passing gear right when it should.
Now I need to finish my front axle and put it in so I can test out the auto in 4wd. :dance:

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