Hello all. I have a problem I just can't figure out. I love my 55 1st series chevy truck 3100 but I can't take it on the freeway, it screams at about 50-55 mph. I have it all original with a 235 engine with a Hydra - Matic auto ****** ( N. 1 - 4.1 - 3.1 - 2.P) open drive with original rear end. My question is what I can do to drive easier on the freeway? I'd like to keep the hydra - matic transmission. If there's no way around it then I suppose I'll change it. It'sa great rreliable truck, I'd like to keep it that way only be able to enjoy the freeway a bit. One last thing: I just bought great 6 lug tires, I know i can throw a camaro rear end on there but using adaptor plates may cause the tires to rub.. Problems. Any suggestions would be great!
Easy to hard.... Choose your route, with only short bursts on the freeway. Taller stock type wheels and tires may help a little. Later rear end with higher gear. Chevy used six lug in half tons to 72 later on some bigger trucks. Check width though. The rears may be a good deal wider after 66. If Particks is still in business a higher ring and pinion can be installed in your rear axle. I would not go higher than 3.00 to one. Overdrive unit?? Car rear but that means adapters or a rear wheel change. Change to a overdrive automatic but to me the hydro makes the truck. good luck.
If I'm not mistaken your original rear end ratio is somewhere around 4.11:1? Check with the aftermarket suppliers, I think Cl***isparts has a 3.55:1 replacement ring and pinion set to fit the 55 1st series. That should help quite a bit. Fasttoys
Patrick's in Arizona also sells gear sets. I used 3:38's front and rear in my NAPCO TF truck. He is great to deal with, the gears come with directions and you can call him direct if you want. He was always very polite and helpful with me.
Change out the gearing in the rear end. My 53 ford f100 has the fordomatic auto trans and a flathead. When I got it, top end was 50mph. I had 3.92 gears. I swapped them out with 3.08 gears and now I can cruise at 70 mph (according to gps).
laugh if you will, I put sound deadener and carpet in my 6 cylinder 57 that screamed at 50 mph.and then it would cruise at 65
Call Patrick's and he will get you set up with taller rear gears. I am going to be facing the same thing sone as I too have an automatic '55 first series. Mine will be going s-10 five speed though. Life without properly spaced gears and an overdrive these days is just not worth living...
well i have a lot of howework to do but you all made it a hell of a lot easier on me so thanks for the advice!! i think I'll call Patricks first and go from there
A 55 1st series I had years ago had the entire drivetrain from a 69 half ton installed, including the rear end. In your case just swapping that out to a higher ratio would make a big difference. Some came with a 3.08 gear which is very freeway friendly, especially with tall tires Devin Posted using the Full Custom H.A.M.B. App!
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