quick 5 speed trans question

I gust got into xjs and now have 2 of them A 2door with 5 speed and a 4door with auto. witch is the stronger trans. bolth are 1990s:dunno:

depends on what you mean by "stronger". also do you know what 5 speed trans you have? ax-15 or the ba-10 ?

no I dont and I dont know how to tell bolth trucks drive but if I consolidate bolth into 1 I will have a good one

my reseaching of my 1990 5 speed trans says it can only be the ax-15.they stopped ba10 production befor 1990 (stopped in 89) and ax-15 started showin up in 88 and continued from there

o btw thats assuming you have a straight 6

Post 3-9-89 should all be AX15s in the XJ, I think.

assuming its OEM and never been changed by the backyard mechanic.
But this still doesnt answer his question "which is stronger"

1990heepxj said:

my reseaching of my 1990 5 speed trans says it can only be the ax-15.they stopped ba10 production befor 1990 (stopped in 89) and ax-15 started showin up in 88 and continued from there

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I'd stick with your preference for auto versus manual. The auto is electronically shifted, so that might be a consideration when merging the two vehicles. You might have to transplant wiring and the trans computer depending on which direction your going. The trannys are also different depending on 4wd or 2wd. The auto is 1" longer so keep the drives shaft and x-fer case linkages with the appropriate trannies.

ya if hes got 4.0s then its only ax-15 from what ever timne in 89 on. if urs is older you probly have a crappy ba10. we need more info on the 2 jeeps to know which trans's you have so we can give you a strength comparison

Im rockin the AX-15. Love it =) iv had an auto xj before and personally prefer the manual trans to the auto. my .02

yup i also am rollin on an ax-15 so far a great trans

just stay away from the GL-5 gear oil, eats the brass... Im running Royal Purple 10w-30 synthetic and love it, shifts great

The AX15 is a decent transmission, only beaten by the NV3550 that went into later model (2000+) XJs and TJs. As far as auto's go the AW4 is a workhorse, just as long as you don't overheat it. That trans got put in a lot of different vehicles, and is very stout. They do NOT like heat though, so run a decent tranny cooler if you do a lot of wheeling, towing, or drive up steep hills often. You will get mixed answers as you see here as to which is stronger. technically speaking I believe the ax15 is rated for higher HP and torque, but as far as wheeling goes I would call it a draw. As I said the only drawback to the aw4 is the heat, usually generated by slippage of the torque converter. The AX15 would not have as much of a problem in that aspect.

Grimm - autos in general don't like heat. You can wreck a THM400 or an A727 in short order by overheating it. I've even seen Powerglides get wrecked by overheating!

To identify the manual transmission, slide underneath and look at the case. The BA/10-5 uses a "clamshell" case, and there will be a longwise parting line down the length of the case at the bottom. The AX-15 uses a "centre plate" case, with the main loading done on a heavy plate, and the front and rear case sections bolted on afterwards.

(In this image, the BA-10 is on the right and the AX-15 is on the left. If you look down almost the right side of the BA-10 case as pictured, you'll see where the case splits for loading. Both units still have the transfer case attached.)


The BA-10 is rubbish - I've wrecked four of them with merely normal driving (it was designed for, probably, the Peugeot 505. It has half the engine, a third the power, and has a kerb weight about eight hundred pounds less than the XJ. Also, the gears are made too hard in the BA-10 - about HRC65 or so - and that's why the teeth end up stripping off of them.) The AX-15 is a favourable transmission, and I'd feel confident towing with it - although I do think there are better options as well (like the NV3550: 2000-2001XJ, 1999-up TJ.) The BA-10 is barely fit for scrap metal in the first place, and it should be serviced (by replacing with an AX-15 or NV3550) at your first opportunity. Besides, getting a new transmission mount cushion borders on prohibitive for the thing...

The only good thing I've found about the BA-10 is that it was easy for me to get replacements - just ask for them and go pick them up. People are probably still getting rid of them left and right. I had to actually swap something for one of the AX-15s I have (the external version,) and we both came out ahead on that one. It will be going in as part of the refit on my 88.

If I remember right my 89 aw4 has a higher rated towing cap. then my 94 ax15

thanks all I am going with the 5 speed I gust wanted to make shure thet it wouldnt brake a week after I put it all together. I do alot of weelin also I found out thet the 4.0 was the only real choice, and I will be doing alot of mods to all of it since I cant leave nothin un tweeked!