Hi, I'm looking for some advise. I have a 63 Chevy C10 pickup with a 283 and a powergride transmission. I'd like to have better freeway gearing and wondered if anyone had infornation on a rear axle ratio change that would work? thanks for your help. Karl
It should already have a 3.08 give or take. What tire diameter and what do you consider to be a good RPM range on the freeway.
The first thing is to actually find out what gear ratio it has now if you don't already know. As P&B said 3.08's were available but that doesn't mean it has them in it. If it has 4.11 gears in it someone may have swapped rear axles at one time not paying attention to the gear ratio and the cure is either finding an axle with 3.08 gears or having the highway gears swapped into yours.
63 truck 12 bolts are the same inside as later trucks (at least into the late 70s). You can change the whole ring& pinion /carrier.You have to use the earlier spider gears for the axle side & use the later pinion seal.I did this in about 88 on a 63 truck with 3.73s useing a rear end from a 75 truck with 3.08s. I cant remember exactly how we swapped around the parts at the pinion but it can be done.Find a real parts man who doesnt mind cross referencing the parts & it should be an easy swap
My 283/PG C10 sings on the highway, but it'll run all day at 80+ mph and gets better than 16 mpg at that speed (probably needs a tuneup). You may not want "highway" gears. 283's need revs to be happy.
63 is a ****rel rear end, with axle shafts that only fit 63. The shafts are usually chewed where the axle bearing rides on them, and those aftermarket "bearing extenders/axle savers" will not fit a 63 rear. But it does still have the welded-on P-bar bracket on the right axle tube. I have done a lot of swaps on those, by using a later 70s-to 87 K10 4x4 6 lug rear. Cut the 63 trailing arm brackets off, as well as the P-bracket, and end up with a rear with real good gear selections; from 2.76 up to 2.5-ish. These rears are about 3/4" wider per side, and it actually fills the wheel well a bit better if you want to swap to 5 lugs, just skip the 4x4 rear and go with 2wd (5 lug) rear from the same years. EDIT: the 63 rear housing is also a one year, and you can't just swap in 64-69 axle shafts, as they won't fit. So, before planning to regear that 63 rear, look to see if your axles are chewed at the outer bearings. ..One more thing on swapping ratios into an older housing: Those later 2-something ratios have a huge diameter pinion gear. GM made a new larger center housing so that pinion can fit. There is no way to grind the insides of an early housing, to make the mid-2's pinion to fit in there. You must use a matching late housing, so that's why a complete rear swap was suggested.
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