Swap 1998 4.0 manual for automatic. How expensive?

Duke-TJ

The Dude Abides
Supporting Member
Joined
Mar 2, 2018
Messages
128
Location
North Carolina
Due to a medical issue I need to give up my 5-speed for an automatic (or buy a late model automatic JK, which is what my wife is asking me to do).
I have a great Jeep mechanic, but am just beginning to consider doing this and have no idea of costs involved.
I'll admit a temptation to get a luxurious 2 door JK, but I've owned my TJ for almost 20 years now. The TJ is MY Jeep. I think this forum will get it.
I've read about the process (Thanks to everyone who has posted on the subject with special thanks to Jerry Bransford for his thorough write-up), but I did not find an estimate of cost.
Whatever the cost, it's Way better than a newer model for sure!
Thanks for any helpful advice!
 
@Jerry Bransford would be the perfect person to ask about this as he swapped his manual for an automatic. He could give you a decent idea of what you could expect to spend.

JKs do indeed have the temptation of being more comfortable, luxurious, etc. However, any time I think about one, I realize that a Jeep is supposed to be a fun, easy to work on, recreational "toy" vehicle. I don't want my Jeep having all these bells and whistles the new ones do. We have our 2015 Subaru Outback for that!

I like my Jeep simple like the TJs are!
 
I have the usual creature comforts in my car. I like the utilitarian feel of the TJ. I just can not imagine Ever getting rid of it.

(Thanks for moving this to the proper forum @Chris)
 
  • Like
Reactions: Chris
I have the usual creature comforts in my car. I like the utilitarian feel of the TJ. I just can not imagine Ever getting rid of it.

(Thanks for moving this to the proper forum @Chris)

That's what I like so much about it too, it feels so utilitarian. I always tell people that I enjoy driving my TJ in the city. When they ask why, I tell them that curbs, pot holes, crappy roads, etc., the TJ isn't affected by them at all. Not to mention I'm riding much higher than all the other traffic, which makes me feel a lot safer and comfortable.

We test drove a lot of JKs and while I do like them, I think they start to feel more like a refined SUV in a lot of ways. Great if it's your daily driver, but our TJ is more of our weekend fun car, so I don't think any of those luxuries are necessary on that sort of vehicle.
 
My cost was maybe $1200 to do the conversion. I spent $800 for the transmission but that included pretty much everything including the torque converter plus all the special hard to find nuts & bolts and shifter. What I had to buy in addition were the transmission cooler lines (which vary by model year) and automatic style mounts. Plus I had to weld the lower transmission mount onto my early '97 skidplate since they didn't come set up to handle both autos & manual transmissions, I don't know if the '98 tcase skidplate came set up for both transmission styles or not. The biggest issue would be finding all the little special parts like the special bolts with low profile hex heads to clear the torque converter that hold it to the crank.

With all those special kinds of parts getting harder to find I'd seriously consider trading that 5-speed TJ for a TJ with the automatic already installed. I personally would not go with a JK but that's a whole 'nother story. :)
 
Thanks @Jerry Bransford . Will try to hold onto My TJ . My Jeep mechanic is amazing, but not cheap. Now that I have a ballpark parts figure plus $1000+-ish in labor, it seems doable to me. 4 JK payments.....
Family still pushing for new model. Son has an '84 CJ7 and a 2015 JKU Willys Wheeler with lots of aftermarket goodies. Though plush, it certainly still is a Jeep
 
Hmm... I too want to change from 5spd to manual but I'll probably wait until it has to be replaced. How might using aftermarket skids affect this? I'm still running the stock, but eventually would be getting either UCF or Savvy which I believe differs for manual/auto trannys.

I think I'm in the same boat as Duke. I have a lot of history with this Jeep, so even if pricier, I'd prefer not to part with what I have.
 
My cost was maybe $1200 to do the conversion. I spent $800 for the transmission but that included pretty much everything including the torque converter plus all the special hard to find nuts & bolts and shifter. What I had to buy in addition were the transmission cooler lines (which vary by model year) and automatic style mounts. Plus I had to weld the lower transmission mount onto my early '97 skidplate since they didn't come set up to handle both autos & manual transmissions, I don't know if the '98 tcase skidplate came set up for both transmission styles or not. The biggest issue would be finding all the little special parts like the special bolts with low profile hex heads to clear the torque converter that hold it to the crank.

With all those special kinds of parts getting harder to find I'd seriously consider trading that 5-speed TJ for a TJ with the automatic already installed. I personally would not go with a JK but that's a whole 'nother story. :)
No need to weld anything to the skid. All TJ 97-02 skids have both sets of holes in them for the trans mount. The Manual mounts sits on the raised rib cross-member in the stock skid and the auto fits onto a mount adapter that bolts to four holes in front of the cross-member.

s-l1600.jpg
 
  • Like
Reactions: Duke-TJ
Thanks @Jerry Bransford . Will try to hold onto My TJ . My Jeep mechanic is amazing, but not cheap. Now that I have a ballpark parts figure plus $1000+-ish in labor, it seems doable to me. 4 JK payments.....
Family still pushing for new model. Son has an '84 CJ7 and a 2015 JKU Willys Wheeler with lots of aftermarket goodies. Though plush, it certainly still is a Jeep
Don't overlook that if your donor doesn't include the auto specific drive shafts, you will need both. The 32RH is the shortest drivetrain length so it requires the longest of the rear drive shafts with the Dana 35 and the shortest of the front drive shafts with the LP 30. It also requires a small diameter tube on the front shaft to keep it off the side of the oil pan on the 32. The hardest part to find will be the adapter harness from the bypassed NSS connector above the trans to the NSS on the side of the 32. If you want to do the swap, start looking now.

If you have SKIM, you will need some programming done. If you don't have SKIM and you buy a PCM with SKIM activated, you will need some programming done.

In this part of the world, I'd break the costs down for an estimate as follows-
Trans with flex-plate, torque converter, stiffener, and crank bolts- 800-1000 and a bunch of that depends on the trans mileage and whether you want to rebuild it. It would be rare to find a low mileage 32 so I'd look for a core and get it rebuilt which would move the price up to 1500.

Drive shafts if you have a rear CV will run about 500 unless you find a donor rig and can snag the stock ones.

Auto PCMs range from 50 to 500. I was just trying to find one for an 05 and the cheapest I found was 750 to get one reman. I finally found one cheaper but purely through luck.

Shift indicator bezels have gone way up, average is 75 to 100 and new is 250 if you can find it.

Belly skid adapters are 35 and if you haven't changed your tranny mount in awhile, a new OEM is 90ish.

ATF is 10 bucks a quarts x 8-9 quarts and you should put a new filter in with a deep pan, so another 100.

If you can find non rusted lines for the trans cooler and are not beat to crap or cut, at least 75 and if anyone finds them cheaper, post up, I need a set.

OEM radiator if you live where radiators matter is 250ish for the auto version.

Don't forget the t-case linkage changes when the t-case moves forward which is a great time to swap in a cable shifter if you don't have one, 160ish. If you don't want the cable shifter, hopefully your mechanic has some of the 32 specific parts laying around from swaps which makes the cost minor.

Prices have changed since Jerry did his many moons ago.
 
No need to weld anything to the skid. All TJ 97-02 skids have both sets of holes in them for the trans mount. The Manual mounts sits on the raised rib cross-member in the stock skid and the auto fits onto a mount adapter that bolts to four holes in front of the cross-member.

View attachment 38873
My very early '97 (mfg date 3/96) skidplate did not come ready for an automatic. A friend who owned a large machine shop company took care of modifying the skidplate enough (I think it was a mill that he used) so I could finish my installation.

I had to weld the mounting plate on in a different position and the mill machined the holes in the skidplate to elongate them. The details of what we actually needed to do are hazy now but the early '97 skidplate mine came with wasn't ready for an automatic as it came.
 
Last edited:
No recommendations for the AW4 swap?
Not really. The AW4 runs hotter, is bigger/longer, and is a significantly more difficult installation like with all the required wiring and clocking of the transmission. The AW4 used to be a more popular conversion but it has fallen out of favor in recent years for the above reasons. I helped on one AW4 conversion together with mrblaine and one of the issues I remember is some wiring colors changed between different model years which made it even more difficult to figure out.
 
Not really. The AW4 runs hotter, is bigger/longer, and is a significantly more difficult installation like with all the required wiring and clocking of the transmission. The AW4 used to be a more popular conversion but it has fallen out of favor in recent years for the above reasons. I helped on one AW4 conversion together with mrblaine and one of the issues I remember is some wiring colors changed between different model years which made it even more difficult to figure out.
Yeah, it was pretty involved when I did mine 8 years ago. I followed Stu's write-up (s) on the swap and basically had only a one wire color issue that revealed itself after the first start up. Once found, it has been flawless (knocks on wood) ever since. Paid 600 for the AW4, sold the NV3550 for 600, and spend roughly 500 for the rest of the items needed including bolts, small parts, etc. I do have two coolers one with it's fan.
 
Yeah, it was pretty involved when I did mine 8 years ago. I followed Stu's write-up (s) on the swap and basically had only a one wire color issue that revealed itself after the first start up. Once found, it has been flawless (knocks on wood) ever since. Paid 600 for the AW4, sold the NV3550 for 600, and spend roughly 500 for the rest of the items needed including bolts, small parts, etc. I do have two coolers one with it's fan.
Did you get the lockup torque converter to engage automatically?
 
Don't overlook that if your donor doesn't include the auto specific drive shafts, you will need both. The 32RH is the shortest drivetrain length so it requires the longest of the rear drive shafts with the Dana 35 and the shortest of the front drive shafts with the LP 30. It also requires a small diameter tube on the front shaft to keep it off the side of the oil pan on the 32. The hardest part to find will be the adapter harness from the bypassed NSS connector above the trans to the NSS on the side of the 32. If you want to do the swap, start looking now.

@mrblaine .
Fantastic, thank you kindly. Between you and @Jerry Bransford and the other TJ owners, I have a better chance of making this work.
I appreciate the help!