Re: Changing from 3 speed to a 5 or 6 speed
 

I was planning on going this route but changed my plans. I don't like having a super steep 1st gear. You can buy the bellhousing off a 68+ GMC v6 (has the large bell housing hole) and use an adapter from Advanced Adapters with a Dodge Gas NV4500. I decided instead of the nv4500, I am going to go with a built AX15 with an adapter. The gear spread is better on the AX15 for what I am after and will shift smoother.

Re: Changing from 3 speed to a 5 or 6 speed
 

Thanks a lot for the information.

Re: Changing from 3 speed to a 5 or 6 speed
 

I put a T5 out of a mid 80's S-10, that still had a mechanic speedometer gear in it, in my 65 and love it. Rather then spend $150 on an adapter plate I just bought a 1/4" piece of aluminum and traced the bell housing and made my own. Also bought a short throw shifter from a place in Nashville, which greatly shortened the stock S-10 shifter throw. Fairly easy swap, and I love those low rpm's at cruising speed.

Re: Changing from 3 speed to a 5 or 6 speed
 

Can you provide details on the AX15 swap? Using the Novak adapter kit? I, too, was looking to the nv4500 for its brute-ish durability, but the 1st gear was a bit too deep for me (want something in low to mid 3.## range), and the massive weight really was not worth it for my uses of maybe once in a blue moon towing a car/Dolly or car trailer.

How does it clear the tunnel, and the rear engine crossmember? Custom fabbed rear trans crossmember? Longer than a muncie/saginaw/t10?

Re: Changing from 3 speed to a 5 or 6 speed
 

Knuckles,
I want to do exactly what you did. A couple questions if you please.

On your T5 conversion you used the original bell housing? From what original trans (SM420)? What did you use for a clutch?

Thx

Re: Changing from 3 speed to a 5 or 6 speed
 

Busted Knuckles: I would like to get more detail from you about your conversion, it sounds as though you use the original GMC bell housing but I as well as wcstory would like to know what clutch you used. I would like to know about what the T5 cost and did you have a 3 or a 4 speed to begin with? With the T5 what rpm ae you turning at 60 mph?
Thanks for any help!

Re: Changing from 3 speed to a 5 or 6 speed
 

Busted Knuckles: I would like to get more detail from you about your conversion, it sounds as though you use the original GMC bell housing but I as well as wcstory would like to know what clutch you used. I would like to know about what the T5 cost and did you have a 3 or a 4 speed to begin with? With the T5 what rpm ae you turning at 60 mph?
Thanks for any help!

Re: Changing from 3 speed to a 5 or 6 speed
 

Considering an NV4500 for my 64 1500 as well. Subscribing to this thread for updates. Mine has the Sm420 4 speed and 4.10 rear gearing. Wonderful up to 55 mph so a 5th gear would be really nice. Only problem I have with the NV4500 is the use of a hydraulic clutch. Mechanical is much easier imop. I was also considering a gear vendors OD just cause they are fun. lol

Re: Changing from 3 speed to a 5 or 6 speed
 

I think the GM NV4500 may have been also used with a mechanical clutch but I think you would then need a factory GMC V6 Automatic trans adapter (hard to find) to use with the GM NV.

Re: Changing from 3 speed to a 5 or 6 speed
 

i don't remember any nv4500 with mechanical linkage, but the older ones used an external slave cylinder. bellhousing has a fork, could possibly be used with mechanical linkage

rick