Swapping from an AX5 to a NV3550 manual transmission in a 97 TJ

Dan T.

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Hi All... Happy New Year!

I have a guy potentially interested in buying my NV3550 from my part out 2001 TJ but he has a 1997 AX5 transmission in his.

I'm assuming this isn't a simple plug & play swap. Any thoughts to the viability of this idea? I really have no idea. I'd like to sell him the transmission but want to help him figure out his options.

Thanks,

Dan T.
 
The better swap would be an AX-15 in my opinion.

The AX-15 should bolt right in as well without issue, not sure about the NV3550.

I wouldn't bother doing this swap for an NV3550. I wouldn't even consider it unless it was a AX-15.
 
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I figured this swap wouldn't be right for him. I'll pass along the info/recommendation Chris... Thanks

DT
 
His tcase is configured for the 2.5L/AX-15 so it has a different input spline count. Neither would be a direct swap without swapping the tcase's input shaft.
Thanks Jerry... I just found specs on both and saw the spline count was off.. You guys are amazing with your knowledge...

DT
 
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No problem! If he is going to do the swap, the AX-15 is the way to go, no question about it.
 
It would if it would fit his 231 tcase. As above, it won't fit.

Oh yes, I just meant to say if he is going to go through the trouble of making it fit (changing the input shaft) and swapping in a different transmission, the AX-15 would be preferable over the NV3550.
 
What do you guys think a fair price for my NV3550 is worth? Probably going to pull it in the next few weeks. It has 124,7xx miles on it. Planning to list on CL or FB Market place.
 
Why are you so adamant about the Ax-15 over the NV3550, @Chris. Do you have a lot of experience with both of them? Is there any documentation that says one is better than the other?
I doubt he has any documentation but many feel the AX-15 is a better/stronger and better shifting transmission than the NV3550 is.
 
Why are you so adamant about the Ax-15 over the NV3550, @Chris. Do you have a lot of experience with both of them? Is there any documentation that says one is better than the other?

I'm basing it off two things:

1) Parts for the AX-15 seem to be much more plentiful. Not to mention the entire transmission is cheaper to replace, see here: https://www.advanceadapters.com/tech-vault/ax15--nv3550/

2) Novak, AA, and all the other places I talked to when researching the V8 swap all seemed to heavily favor the AX-15 as the manual transmission of choice for V8 conversions in Jeeps (yes, I know that V8 swaps don't really amount to much in this case). Take that for what it's worth of course. Novak regards it as the best five speed transmission ever installed in a Jeep: http://www.novak-adapt.com/knowledge/transmissions/manual/ax15/. I think a lot of this just has to do with the fact that it's the more available and cheaper transmission of the two.

I'm not trying to say the NV3550 sucks, I'm just saying if I was going through the hassle, I would put in an AX-15 over the NV3550. Not trying to rip the NV3550 at all, I'm just thinking in terms of the more available of the two transmissions and the price point.

@Mark K also mentioned at one point that he had to have his NV3550 replaced, and the dealer wanted $3500 for a new one, whereas Advanced Adapters wanted less than $1500 for a new AX-15. He took ended up replacing his NV3550 with the AX-15 last I read.

I'm not trying to say the AX-15 is better, it's just more widely available it seems like... and a lot cheaper too!

If I had an NV3550 and it needed to be replaced, I'd swap it out for a AX-15, that's all I'm saying.

I've edited my original post to remove the word "better". That was a poor choice of words.
 
Update.. The interested party has an AX15 (I was mistaken) and will be able to use my NV 3550. He's a friend of another Jeeper so we'll be taking it off my donor Jeep this weekend and trading wrench time for the transmission. I've been nibbling around the edges selling off the little stuff but time to tear into and and start moving the big stuff.
 
If it's a 1997 4 cylinder with a manual transmission, he definitely has the AX-5. Worth confirming though!
I am so confused. Since when does any transmission behind the 2.5 bolt up in place of any transmission behind the 4.0? Do ya'll know what the bellhousings look like between the two?
 
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I am so confused. Since when does any transmission behind the 2.5 bolt up in place of any transmission behind the 4.0? Do ya'll know what the bellhousings look like between the two?
4.0 to 4.0 in this case.
 
I am so confused. Since when does any transmission behind the 2.5 bolt up in place of any transmission behind the 4.0? Do ya'll know what the bellhousings look like between the two?

Now I’m confused. I know the bellhousings are completely different between the 2.5 and the 4.0.