Any NV3550 or AX15 swappers out there?

[Grantshire]

There are plenty of write-ups and information on NV4500 swaps but I am curious if anyone has swapped a NV3550 or AX15 into a FSJ. In particular, has someone put either of these medium duty 5-speeds behind an AMC V8? If you have, would mind posting up some details and a picture of your shifter? Also, what transfer case did you go with?

[Cecil14]

I intend on putting at least an AX-15 (NV3550 if I can find one) in my J-10 behind the stroker for at least next winter. They're not as beefy as the NV4500, of course, but the NV3550 was used in Dakota V8s if I'm not mistaken. They should hold up alright. I wouldn't try dragging any semis around, though.



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[Billygoat]

I have a 3550 in my garage waiting warmer weather - going behind a 360, and mated to a 300 tcase

Look for a 2001 Cherokee with a 4.0 and manual - the NV3550 has a different output bolt pattern, but other wise the same - less commom but I got 1 with 23k on it for half what they wanted for a Wrangler 1 with 45k.

Also if you can score the bellhousing it will bolt right to your block, just need the correct pilot brg and clutch disk.

[Cecil14]

The output bolt pattern should be the same, it's just the standard round NP 6 bolt pattern. The clocking on it may well be different, though.


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[mdill]

Planing on a 4.0+NSG370(six speed) + Dana 300 swap this summer (Get that up and going before the 4.6 stroker swap)
From what I understand you may or may not need to swap the D-300 input shaft and a clocking ring is needed.

(Hopefully BJ's can fix me up on the tranny to T-case stuff when I figure out exactly what is needed)

the 3550 has a good rep. i will see how the NSG holds up. If it toasts then I will go to the 3550.

Mike D.

[JeepsAndGuns]

The output bolt pattern should be the same, it's just the standard round NP 6 bolt pattern. The clocking on it may well be different, though.


aa

Correct. The bolt pattern is the same between the wrangler and cherokee, just the cherokee version has a slightly diffrent clocking.

[Grantshire]

Okay, the AX15 5 speed has been around since the late 80's and is a relatively easy swap behind a Jeep engine. That's almost 20 years but I have never seen or read of one swapped into a FSJ (or a NV3550 swap). Why not? Can't be strength, both are considerably stronger than the T5 and T176/177 Jeep put in some of the FSJ's.

"Use a NV4500." A lot of us have this transmission and love it (got one in my M715 behind a 6.2 diesel). But its not the best 5 speed for all applications. If your axles are geared low the NV4500's granny low is worthless for a DD. That leaves you with a 3 speed transmission with overdrive.

Considering how long the AX15 and NV3550 have been around isn't there someone in FSJ land that has first hand experience with one of these swaps?

[Cecil14]

I would guess strength to be the big issue. When you come down to it even the NV4500 really isn't anywhere near as beefy as the old granny 4 speeds. Yah, the AX-15/NV3550 are worlds ahead of the T-5 and T-176, but they still don't compare to a T-18 or an SM465.

I'm going to run one just because they're loads cheaper than an NV4500 and like you say, a lot more "rounded" as an all around driver. I don't tow all that much with my truck, I'm going for more fun to drive than anything else. The T-18, while ungodly strong, is absolutely painful to drive.


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[Kris]

You cannot use a v8 flywheel with this swap.
The v8 flywheel protrudes farther off the block and interferes with the throwout bearing.
You need to use the 4.0/4.2 flywheel and have it rebalanced to the v8.
Its a simple match balance. Nothing to it.
After that you will need to use the 4.0 mitsu starter unless your v8 already uses one (88+). The 88+ v8 and 4.0 use the same part number for the starter.

The other thing to consider is that unlike an nv4500 swap, you must convert to a hydraulic clutch setup so hydroboost will be in your future.

kris.

[Greg Taylor]

I intend on putting at least an AX-15 (NV3550 if I can find one) in my J-10 behind the stroker for at least next winter.

Hi Anthony,
Would you mind if I stop by sometime and look at your set up? I have been mildly considering swapping the entire TF727 & NP228 from my 1989 Grand Wagoneer, while I have the engine out for the 304 V8 stroker build, and swapping in a 5-speed AX15 or NV3550 or possibly to a T18/NP208 set up.

I?d be interested in seeing the set up in you J-truck. What?s in it right now?

[Cecil14]

Hey Greg,

Yah, you're more than welcome to stop by. Only problem is I don't have an AX-15 just yet. LOL I've got a D300 that I had behind a T-5 a while back. Right now I'm running a T-18/D20.

I have already switched over to the 4.0L flywheel and starter. Hard lesson learned there. lol I'd like to switch to the AX-15 at the same time I do the 4.0L FI. Then I could just run the CPS in that bellhousing.

Ok, hijack over.

[Billygoat]

You cannot use a v8 flywheel with this swap.
The v8 flywheel protrudes farther off the block and interferes with the throwout bearing.
You need to use the 4.0/4.2 flywheel and have it rebalanced to the v8.
Its a simple match balance. Nothing to it.
After that you will need to use the 4.0 mitsu starter unless your v8 already uses one (88+). The 88+ v8 and 4.0 use the same part number for the starter.

The other thing to consider is that unlike an nv4500 swap, you must convert to a hydraulic clutch setup so hydroboost will be in your future.

kris.

WHOA!!!!! I talked to 3 big conversion kit shops and not 1 said anything about the flywheel with a 3550 or 4500 swap...where did you get this info?

As far as hydralic that is a maybe....there are kits to hook a 3550 to a T176 bellhousing and retain your factory mechanical linkage.

[Cecil14]

If you run the factory 4.0L hydraulic clutch then you'll need to run the 4.0L flywheel. A hydraulic clutch doesn't have near as much play as a mechanical one and is more sensative to change.


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[Billygoat]

I called Novak, and they were confused never heard or such a thing, said you HAVE to use a 360 Flywheel on a 360 Engine.

I am just trying to make sure I have all my ducks in a row before I start my project...........

[Cecil14]

No you don't HAVE to use a 360 flywheel on a 360. All the AMC flywheels (Gen III V8s and L6s that is) are indexed the same. The problem is that the V8s are externally balanced, meaning the flywheel has to be balanced for the 360. If you take an L6 flywheel (neutrally balanced to start with) and your 360 flywheel to a speed shop they can match balance them. Now you can run your 4.0L flywheel on your 360.


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