Best Gear Ratio for Overdrive Trans
 

Just kicking around some ideas...

I'm swapping in TBI 454 into my '77 dually and now I'm seriously considering swapping over to a 4L80E trans. I'm curious what the consensus would be regarding the optimal gear ratio for that particular setup.

It's a Dana 70 HD rear end. I'm assuming it's got 4.11's in it now, although I never bothered to check. Tire size is 225/75/16.

Any thoughts?

Re: Best Gear Ratio for Overdrive Trans
 

I went on Randys Ring And Pinion 55mph= 1833rpm
65mph= 2167rpm
75mph= 2500rpm

Re: Best Gear Ratio for Overdrive Trans
 

Best gear ratio for what? Towing, fuel mileage, acceleration?

Re: Best Gear Ratio for Overdrive Trans
 

General purpose.

Re: Best Gear Ratio for Overdrive Trans
 

I like 3:73. But that's just me.

T

Re: Best Gear Ratio for Overdrive Trans
 

I also like 3:73's. They work great for towing but don't make the engine scream down the highway like 4:11's.

Re: Best Gear Ratio for Overdrive Trans
 

I have 4.10's now with a 454...

Don't plan on doing much highway travel, and if you do make damn sure you know where your next fuel station is... you won't be passing many

I personally am going to re-gear it because although i tow on a regular basis 4.10's are just not needed.

How ever i only have a Turbo 400... I can't comment on it if you got that extra gear in there. I think it would certainly be tolerable