Help me pick a transmission

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lpukas2
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Location: Vail, AZ

Help me pick a transmission

Post by lpukas2 »

Planning on a 5.7 Hemi swap into the 72 J4700. I really wanted a NV4500, but after researching I am pretty limited on years. Somehow find a 03-05 NV4500 with bell housing and clutch out of a 5.7 Gas 2500 / 3500 or spend a ton of money on converting a 96+ GM or Dodge diesel NV4500 over to the hemi. My second thought is picking up a Jeep NV3550, parts are readily available and swapping it to the Hemi is straight forward. Third choice is finding a Dodge NV3500 and forth is using a Jeep AX-15. Truck will be a daily driver with 31" tires, no offroading or anything stupid.

Any thoughts if any of these transmission with the exception of the NV4500 will live behind the 400 HP / 400 TQ of the Hemi on a daily?

Not finding a lot on this topic and the little I do find is all over the place.
72 J4700 (Duke) Eagle Head 5.7 Hemi/NV4500/NP205 in progress
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akguy09
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Re: Help me pick a transmission

Post by akguy09 »

Tremec 4050.....seems like a good option, depending on your budget
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Yeller
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Re: Help me pick a transmission

Post by Yeller »

I really like the tremec 4050 but for the price point you can purchase a new nv4500 for less than half and purchase a bell housing that will work, assuming there is one out there for the Hemi (I have not researched that). Often I find that there are options out there that no one wants to discuss because it removes the need for their expensive parts, but I have not researched the hemi. As for the AX15, on paper it doesn't do the job, however in reality I know a lot of them are out there living happy lives in 5000# trucks with similar power levels and the owners love them. They are also avail brand new from Aisin for a very reasonable price. For smooth easy shifting in a DD the 4050 or AX15, if you can deal with long slow shifts but extreme robustness, the nv4500. My only complaint with either the 4050 or the NV4500 is the gear splits are wide and for street driving 1st gear is not needed.
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BaldBeardedBastard
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Re: Help me pick a transmission

Post by BaldBeardedBastard »

^what he said- I am a fan of the AX15 and they have held up behind plenty of V8s.
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lpukas2
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Re: Help me pick a transmission

Post by lpukas2 »

I'm starting to lean towards a ax-15, you can pick up a brand new one from Novak for less than the used price of a NV4500 and that is not including changing the configuration of it if necessary. I would love a Tremec but its more than I want to spend. Even a used NV3550 is about the price of a new AX-15. Thinking back, I really loved the one I had in my first YJ. Not to mention, parts are easy to find for them.
72 J4700 (Duke) Eagle Head 5.7 Hemi/NV4500/NP205 in progress
02 TJ: 4.0/32RH/Atlas on 14" ORIs and tons.
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Stuka
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Re: Help me pick a transmission

Post by Stuka »

The AX-15 has an input rating for 300hp/300lb ft. It can live behind engines with more than that if you don't abuse it, or put it under heavy load (towing or the like). The NV3550 has the exact same input rating. The NV4500 for comparison is rated for 460lb ft. Though they regularly hold up to way more than that.

But given normal driving, an AX-15 should work ok behind a stock 5.7 Hemi.
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boomersrule55
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Re: Help me pick a transmission

Post by boomersrule55 »

I have researched the NV 4500 for my GW-4BT swap and for what they are asking for the NV 4500's with no warranty, your are better off with a TR 4050 they are rated for 600 ft flywheel torque and 15k towing and it weighs 100 lbs. less, Silver Star sells them for 3200 + shipping, pricey I know, but it's new! BTW I saw a Dodge NV 3500 with T-case in AZ on Facebook marketplace recently for 1500... to light for my 4bt, going to buy a 4050.
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