Topic: 14 bolt chevy gears

[bigbird110]

I'm running a 14 bolt chevy rear end with 4.10 gears. The truck has a chevy 305 engine with a 350 transmission. It runs real high RPMs at about 60 mph. My question is am I better off to change transmissions or will I be just as well off to change my gears to 3.42. The gear change would be more expensive but a lot less work than changing shifter, trans mount and driveshaft. A 3.42 is the highest gear I can find for my rear end I just wondered if y'all think it will make a difference? Thanks

[lowboy]

think the OD tranny would make you happier as the 4.10 would still give you the Umph off the line and OD would get the mileage up with a slower RPM

[miraclepieco]

What RPM's are you turning at 60 mph? How much highway driving do you do?  You have to decide if revving higher than normal on the highway is worth the work and expense of a rear end or transmission change. Maybe you could learn to live with it? Bigger rear tires would help a little.

That being said, I definitely go with the gear change.  Should be cheap and easy to locate a set in a wrecking yard.

[hotwheels]

I would change the gears.

[bigbird110]

At 55 mph I'm at 2800 rpm's. I talked to a transmission mechanic who told me he had the same issue and the overdrive tranny made little difference because he was still low geared. He said his truck would be through 3 gears before he got under a red light and then shift to overdrive. So I have decided to go with gears first thanks for the comments I will let y'all know what happens gears should be put in by the end of the week.

[Jeepenstein]

Tire height choice optimized first, 4 speed overdrive trans second and gears tailored to bring it all together.

I will be running 32" tall tires with a 4R100 (0.71 to 1) trans and 5:25 gears.

I can live with 2300 RPM at 60mph.

Jeff

Ps you can play here:

http://www.csgnetwork.com/multirpmcalc.html