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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: bob77 on August 21, 2008, 11:10:04 am

Title: 77 3-Speed
Post by: bob77 on August 21, 2008, 11:10:04 am

Hello all,
I have a 77 Short box with a 250 and a 3-speed manual. The truck gets terrible fuel mileage for a 250. It does have 4.11's in the rear end and I will be swapping the rear end for a higher ratio rear end. I am just wondering if there was more than one 3-speed made for these trucks. Could part of my low gearing be in the transmission as well? I don't believe so, but I would like to make certain.

Thanks

Title: Re: 77 3-Speed
Post by: Captkaos on August 21, 2008, 11:28:27 am

Nope, it is all in the rear.  I had the same setup and swapped the I6 for a 350 and then the rear for a 3.42 and then the 3 speed for a 4 speed.  It is all in the rear ratio.
You could however keep the 4.10 and swap to a T5 trans with OD.

Title: Re: 77 3-Speed
Post by: bob77 on August 21, 2008, 11:42:47 am

Thank you sir. I have another truck with higher rear-end gears (I haven't checked yet to see exactly what they are). It has the same engine and tranny, but just does so much better on the highway (far less drag when letting off the gas). So aside from some time and elbow grease, the rear end swap will cost me next to nothing. I'd like to have a 4-speed behind the 250, but that will have to wait for awhile.

Thanks a bunch