5-speed swap

[SenorCole86]

Hey guys, my 4-speed is starting to make funny noises, and I'm contemplating swapping in lower gears in the axles too, so I think it may be time for a 5-speed. I did a little research and heard a lot of good things about the NV4500. How easy are these things to find, what will it take to get it between a dana 300 and a 258, and is it even the right choice? Any help at all would be greatly appreciated. Thanks a lot guys, have a good one.

 

[yjdave]

Need a adapter for the motor or a different bellhousing. not sure on the d300, might bolt up. Have you thought about ax-15 or nv3500 from yj/tj??? Alot cheaper and thry will bolt up.

 

[BaconYJ]

The NV4500 is a monster and will require addapters for probably both the bellhousing and the TC. You will aslo need to do some major cutting on the body to allow it to fit or have a decent size body lift. As yjdave said look at the ax-15 or the nv3550 (same thing for the most part). Much smaller in bulk but still a great transmission.

Bacon

 

[Bounty__Hunter]

Throw in a t5, shouldn't need any adapters.

 

[SenorCole86]

Do you think the t-5 is sturdy enough to stand up the abuse I'm liable to give it?

 

[Bounty__Hunter]

Yes, the t5 has a bad rep but will hold up.

 

[Sparky-Watts]

Do you think the t-5 is sturdy enough to stand up the abuse I'm liable to give it?

Sure, so long as you don't try to pull a wheelie over those mall speed bumps, it should be fine! :lol: :lol: :lol:

 

[PhattyX]

I have a t5 behind a 360 v8. It's held up fine to a lot of abuse, both on and off road. After the opinions I've read about it, I was expecting it to have blown apart by now.

-X

 

[Bounty__Hunter]

Buddy of mine has on in his CJ behind a built 5.3L out of an '00 Chevy, holding up just fine. Another buddy swears by them, and usually runs a sick amount of GM HP through them.

 

[SenorCole86]

Well alright, I have a whole new respect for this transmission. What should I look for as far as donor vehicles? The little bit of research I've done suggests these can be found in Ford and GM vehicles as well? Will these incarnations of this transmission bolt up as well?

 

[Bounty__Hunter]

I'm out, that's all I've got. Don't have any real knowledge of parts availability or interchangeability before '87. Sorry.

 

[Joe Blow]

Hey guys, my 4-speed is starting to make funny noises, and I'm contemplating swapping in lower gears in the axles too, so I think it may be time for a 5-speed. I did a little research and heard a lot of good things about the NV4500. How easy are these things to find, what will it take to get it between a dana 300 and a 258, and is it even the right choice? Any help at all would be greatly appreciated. Thanks a lot guys, have a good one.

Advance adapters sells an adapter kit to get the 4500 into a 258/300 configuration (I believe it's about $500). The transmission you want (it comes in different versions) is out of a Dodge 4x4 DIESEL 95 and up. The GM version of the transmission requires you to swap the output shaf to mate with the Dana 300 whereas the Dodge version bolts right up. The floor will also have to be cut to accept the top housing and shifter assembly of the 4500. Honestly the 4500 is definite overkill in a 258 considering it's built to take a 10cyl Cummins Diesel.

The AX-15 is a good choice for the 258 and will bolt up easily. You will require a clocking ring and pilot bushing (about $200 for both) from an
adapater maker like Novak to make it fit, but the bellhousing bolt pattern will bolt right up to the 258. You will however, have to convert the clutch assembly to hydraulic. The 86 CJ 4cyl (not sure of other years) came with a hydraulic clutch setup and parts are cheap. Also the skid plate/transmission crossmember will have to be fabbed as the transmission mount locations are different since the AX-15 is longer. If going the AX-15 route make sure to get the later model version 1994 +; the earlier versions (89-93) used an internal slave/bearing arrangement and were not as strong as the later external slave type.

Lastly the T-5 is obviously not as strong as the other two transmissions but it really depends on what you're doing with it. Some people have had luck and their T-5's last forever, others blow them up in weeks. The benefit of this is there is no fab required, it will drop right in.

Hope this helps.

 

[BaconYJ]

http://www.novak-adapt.com/index.htm is another good sight for information on trannies and TCs. They have addapters for most as well.

Bacon