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| | | | Joined: Aug 2015 Posts: 16 New Guy | | New Guy Joined: Aug 2015 Posts: 16 | Hi,
I recently acquired a 1960 GMC 1/2 ton flatbed with a 235 stovebolt, 4 speed transmission with granny gear...
I have been told; a T-5 Borg-Warner should bolt up correctly and run well with this nice little truck.
Right ?
Also, I am wondering how to identify what rear end I have in it. Posi-trac or not ?
Help, please.
Thank you.
Whatever you are doing, have a good time at it..... Ya gotta do it anyway... So, enjoy life !!!!
| | | | | Joined: Sep 2011 Posts: 2,951 'Bolter | | 'Bolter Joined: Sep 2011 Posts: 2,951 | Many of the truck owners here, myself included, are enjoying the T5 transmission for daily driving. Not a good choice for hot rodding as it will not stand up to abuse.
Another choice might be an early 3 speed with the solenoid OD (sorry but I can't remember the name).
Finding an S10 T5 that will allow you to keep the factory cable driven speedometer can be a challenge. If that is not an issue for you, then finding a T5 that fits will be a lot simpler. You just need to find the right gearing combination for your particular rear diff gear.
A Muncie pattern T5 can be made to bolt directly to your bell without an adapter plate, keep your same clutch package, shorten the drive shaft and cut a hole in the floor for the shifter. Here's a post of my T5 installation in my 1965 C10.
My signature link will take you to my BLOG with plenty of info on the T5.
Last edited by Lugnutz; 08/16/2015 6:10 PM.
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Not the motor that came in truck. The only real way to know what diff is to take off cover and read ratio on ring gear and examine for posi clutches. There are other "ways" to see wheel spin and count revs but go ahead and change fluid and check.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Aug 2015 Posts: 16 New Guy | | New Guy Joined: Aug 2015 Posts: 16 | Hey,
Thank you much !!!!!
Exactly what I needed to learn...
Thanks again,
Whatever you are doing, have a good time at it..... Ya gotta do it anyway... So, enjoy life !!!!
| | | | | Joined: Aug 2015 Posts: 16 New Guy | | New Guy Joined: Aug 2015 Posts: 16 | Was it originally a 261 ?
I'll do the spin on the rear wheels..
Thank you
Whatever you are doing, have a good time at it..... Ya gotta do it anyway... So, enjoy life !!!!
| | | | | Joined: Aug 2015 Posts: 16 New Guy | | New Guy Joined: Aug 2015 Posts: 16 | Hello again,
I am looking into getting a used T-5 and having it rebuilt. my question is: what year and model T-5; will work best for my truck... I have a 1960 GMC 1/2 ton flatbed.. with 235, 4 speed heavy duty trans (currently).
any suggestions, or do I need the rear end gear ratio, also ?
Thanks,
Whatever you are doing, have a good time at it..... Ya gotta do it anyway... So, enjoy life !!!!
| | | | | Joined: Sep 2011 Posts: 2,951 'Bolter | | 'Bolter Joined: Sep 2011 Posts: 2,951 | The rear diff gear is important. Probably a 3.73 but it will make a difference. Also, what tire diameter will you run? A 235/75R15 is common for these trucks. That's a 29" tall tire. | | | | | Joined: Aug 2015 Posts: 16 New Guy | | New Guy Joined: Aug 2015 Posts: 16 | Please allow my self correction ....
I have a 261.... not a 235 engine..
Thanks,
Whatever you are doing, have a good time at it..... Ya gotta do it anyway... So, enjoy life !!!!
| | | | | Joined: Aug 2015 Posts: 16 New Guy | | New Guy Joined: Aug 2015 Posts: 16 | Hello,
My OEM shop manual says it is either
a 3.90 = 3300 axle cap
or 3.38 = 3500
It is a heavy duty flatbed 261 4 speed.
model C-14 or C-15
help !!!!
Whatever you are doing, have a good time at it..... Ya gotta do it anyway... So, enjoy life !!!!
| | | | | Joined: Sep 2011 Posts: 2,951 'Bolter | | 'Bolter Joined: Sep 2011 Posts: 2,951 | If you have a 3.38 rear then you should look for an S10 truck T5 with a 0.86 OD gear. That will give you ideal highway RPMs at cruising speed. If you have the 3.90 rear then the 0.73 OD gear is best. 1988 and earlier S10 T5s are very hard to find but if you get one it is most valuable for the cable speedo connection on the tail stock.
The 1989 thru 1993 S10 T5 will also work but won't have a cable speedo hookup. | | | | | Joined: Aug 2015 Posts: 16 New Guy | | New Guy Joined: Aug 2015 Posts: 16 | As you know, this isn't an easy to find item ( T-5 )...Wondering... will an 88 S-10 Blazer 2-WD tranny fit? And have the gears, I need ?
Whatever you are doing, have a good time at it..... Ya gotta do it anyway... So, enjoy life !!!!
| | | | | Joined: Sep 2011 Posts: 2,951 'Bolter | | 'Bolter Joined: Sep 2011 Posts: 2,951 | As you know, this isn't an easy to find item ( T-5 )...Wondering... will an 88 S-10 Blazer 2-WD tranny fit? And have the gears, I need ?
Last edited by Lugnutz; 08/18/2015 7:44 PM.
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