nv3550 vs ax-15

So i have decided to replace my failing ax-15 with something else. After having been rebuilt in 2004 by the previous owner, then in late 2006 by me, never having shifted right, it now makes a whirring noise in 4th and 5th gears and clicking/banging at speeds above 30mph, I am done messing with it. I figure i have two real options, either a rebuilt ax-15 (which i am leaning against because of issues with mine) or a new/rebuilt nv3550. So my question is:
those with the nv3550 (2000-2005 5 speed with 6 cyl), have you had any issues with it?
How many miles on it?

Those with the ax-15 (89-2000 wrangler 5 speed with 6 cyl), have you had any issues with it? how many miles?

Thanks guys.

Yeah I feel your pain with the AX-15 issues. I'm on my third trans as well. The first I burnt up myself ragging on the jeep with little tires ( the good old days ) Then I had it rebuilt and new clutch installed and drove 3 years on a 5 inch lift and 35's with stock gears. I trashed the clutch and work the trans for all it was worth till 20K later it gave out on me. I bought my last one from some guy in Westminster for 500 bucks with the bell housing and shifter. So far its running great he said he just had it rebuilt but was going auto. I know that all trans problems I have had with mine have been 100% my fault and saw them coming. My current plan is to rebuild my old trans myself and see how it goes. Parts are cheap and the design of the trans is simple. If I have the money I would step up to a NV4550. I have heard good things about the NV3550 but not enough to want to spend the money or really research the swap. Keep us posted on what direction you go.

since i have the 94, it is very close to bolt on.
A modification to the transfercase shifter where it attaches to the transmission must be made and the reverse light wires need to be spliced into each other.

The cost at the moment is about the same for both. I will not be rebuilding the ax-15 that I have. That is no longer an option because i know that it will break down with in 15000 miles.

The cost for a rebuilt ax-15 or a nv3550 is about the same. On ebay, i know i know, a new nv3550 boes for about 1000 shipped. A rebuilt ax-15 froma shop is about 1100. A new nv 3550 runs anywhere from about $1500 all the way up to $1800.

There is another option as well for a bit more. RSgear makes a ax-15 that is a bolt in replacement. The difference is that they stuck the internals from a toyota supra transmission inside of it. That runs about $2100 plus shipping.

The thing i am worried about with the nv3550 is how long it lasts before it starts having issues.

Thanks again guys

are you planning on pulling the trans out yourself. there should be a shop that will do a rebuild for alot less for a 1000 bucks

yea
i have taken it out a couple of times.
It was rebuilt back in 04 by the previous owner
That rebuild lasted about 30k.
Then i put all new synchros and bearings in it
That lasted about a year.
So i am just tired of my transmission. I'm not against putting another ax-15 in it, just not the one that is in it now.

I would rather put a nv3550 in it because 1st is a little lower, the overdrive is a little higher, its basically the same price for either, and the nv3550 can handle about 75 ftlb more torque than a regular ax-15

I rebuilt it myself for around $350 with a new clutch. All the shops that i called around me quoted me over $1200 to rebuild it at the time.

When I called ATLAS about possible problems with my drivetrain they said if I find the problem is the transmission I should go with a 3550. I don't remember why but I think they said it is a little stronger and has a better first gear ratio. Again cobwebs but they definitely said to swap.

Thanks for the info guys this might make me change directions with the next trans.

Here is some info I found on the 3550.
The NV3550 is manufactured by the same company that makes the 4500, it is a lighter duty transmission, with dimensions almost identical to the AX-15, which is'nt surprising, because this transmission was designed as a replacement for the AX-15 when Jeep stopped using them in 2001. Jeep TJ's with the 4.0 and a 5-speed manual from 2001 to 2005 came with the NV3550 stock. This makes it an excellent swap for a YJ with a 4.0! You get a sturdier transmission, at an affordable price, and its almost a direct bolt in replacement. It's got the right input shaft to accept the 4.0, the correct bolt pattern for a YJ or TJ 4.0 bellhousing, and the correct output shaft and bolt pattern for the NP231J. Because the dimensions are so similar to the AX-15 it will fit between the existing skid plate and body, and you wont need to change driveshafts. If you have an older YJ (1992 or older) with a 4.0 you'll also need a bellhousing that supports an external slave cyl. You should be able to scavange one off of any 1993+ wrangler that came with a manual trans and a 4.0.

the only thing with the nv3550 is that they had problems with it in the 2000 models. It was supposed to be fixed by 2001. Some of the tj owners have had shifting problems by 50000 miles. Many of them had 2001-2004 nv3550. I am probably going to go with a nv3550,but i was trying to get some peoples personal experiences with it to see if they have had any problems. The nv3550 is also a very popluar swap into a early bronco.