Changing from 3 speed to a 5 or 6 speed
 

I have a 64 series 1000 with the 305E engine and the fully synchronized 3 on the column. I am considering changing to a 5 or 6 speed so I can get better gas mileage out of it. If anyone knows of a transmission that can be used for this please let me know what it is and if you know where to find one I would be thankful for that information also. Hoping to get good news soon. Here is what I am working on. http://6066gmcclub.com/forum/attachm...1&d=1438365698

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

hi and good morning, have put a Borg Warner T5 in my 62, was fairly easy conversion, with lots of info on the net, used one out of 1987 S10 truck, the 5speed is over drive, had to shorten drive shaft, and add the adapter plate to the bell housing, works awesome

For those that work your truck , or tow, it may be a little light duty, for the home depot runs it is well suited.

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

Thanks for the information. I will check into finding a T5 where did you get your adapter and do you know the part number for it?

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

hi Paul Got my T5 from wrecked S10, bought the whole truck for 400$ was in a V6 version 1987 need the older models newer ones have the bell housing right on the tranny
The adapter is just a aluminum plate to position the tranny further back to accommodate the longer input shaft on the T5, you will need different clutch to mate with the spines on T5
Will check and see where I got the adap. plate from and get back to you, will also check some websites for tranny info which will help you a great deal JM

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

Thanks again for the information and I appreciate you looking for more info for me. If anyone else has other info that might be helpful I would appreciate hearing from you also.

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

Paul:
Just my two cents, but the easiest swap to get an overdrive gear and some better mileage is a 3 speed with overdrive tranny. They were used from about 1955 through about the late sixties. They use an electric solenoid to shift the transmission into overdrive. There were two versions, an early non synchro version with the 4 bolt side cover and the later synchro version with a seven bolt side cover. I have the later synchro version in my truck. Read all about them here:

http://www.classictruckshop.com/club...5n/rebuild.htm

Regards,
Steve
New Orleans

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

Thanks for this information. Do you have any idea where one of the synchronized ones can be found and about what they are going for?

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

Paul:
I bought mine a few years ago for $150 with $150 shipping. I have seen them from $150 to $1000. Somewhere in the middle is likely the right number. Two parts on the tranny are getting a bit tough to replace, thus you should be sure that they have those parts and they are in working condition. The first is the governor switch that sticks out on the right side of the tranny. The second is the solenoid that sticks out on the left side. If you need to ship one of these, you should have both removed to ensure that they are not damaged (ask me how I learned the hard way with UPS). It will take a bit of scrounging to find one, but Craigslist and Ebay are the two places that I see them pop up. These trannies will bolt in place of the three speed that you have currently.
Regards,
Steve
New Orleans

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

Steve: thanks a lot for the information. Now to see if I can find one.

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

HAS ANY ONE PUT AN OVERDRIVE NV 4500 TRANS OUT OF A LATE 90S OR SO CHEVY IN PLACE OF A 4 SPEED IN ONE OF THESE TRUCKS. I HAVE A GOOD ONE, AND OVERDRIVE WOULD BE GREAT IN MY 66 1500.:headscratch:

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

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

I know this a little different than everyone else, but I used an "Aisin AR-5" 5 speed from a 2009 Colorado on my 1965 shortbed. I used a stock bell housing with a home built adapter plate and hydraulic clutch also the driveshaft had to be shortened. This lets me get 2100 RPM at 75MPH. It's a tight fit with the stock bench seat, but Core shifters makes a short throw shifter that uses Hurst shift levers of many different bends.

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

So the T5 is a great choice but the ideal match is a T5 out of a mid 90s camaro coupled with the S10 tailshaft with the mechanical speedo, the adapter ring and shortened drive shaft. The camaro T5 has a higher Horse Power rating and a better OD ratio, the S10/S15 tail shaft puts the shift lever through the floor in the old position instead of through the seat, lol. As for the funky angle that the shifter comes through, a lil heat in the right spot, or use a bending unit and position it anywhere you like.

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

Thanks for the replies about changing my transmission but I have decided to leave the 3 speed in it at least for now. I have a T5 from an S10 the electronic speedometer drive if anyone is interested.