Th350 with 4.10 gears in the rear

[dhamilton62]

Anyone know how the gearing would be if I threw in a th350 trans into my 62 c10? I believe the gearing is 4.10, and it's got a 350sbc in there now. Would the overdrive help out on highway cruising? Thanks!

[jayoldschool]

TH350 is not overdrive. Your RPM in 3rd (high) would be the same as now. Look for a TH200-4R or a TH700R4 (4L60).

[siggyfreud]

I drove with a th350 and 4.10 for awhile. Definitely much more comfortable with the 700r4 at highway speeds. As mentioned, the th350 has no overdrive. Third gear is 1:1.

[dhamilton62]

Thanks for the tips on the transmissions. If I can't change my rear axle gears, would getting a new rear end, like a Dana 44 with options of gears be a better choice? If so do you know what would fit a 62 C10 long bed? Thanks

[tincan1966]

I'd swap out to the 67-72 12 bolt rear axle- it's a bolt an and lots of gear choices for the series 3 carrier.

[Captainfab]

If the differential in your '62 is original it is a Eaton HO32 and the gears are likely 3.90's. I would change it out for a '63-'70 12 bolt, or a '71-'82 12 bolt if you want to change to the 5x5 wheel stud pattern. There is much more aftermarket support for the truck 12 bolt and it is easier to find highway friendly gears. Either way, the trailing arm mounts will have to be moved to align with your '62 trailing arms as they are farther apart than the '63-'72 trucks. Then depending on what year 12 bolt you get, you will need either a custom length panhard bar, or weld on a mount to use your original panhard bar. Also keep in mind that the late'70-'82 12 bolts are 1.5" wider than your Eaton HO32.