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smokshwn
01-04-2005, 08:11 AM
I apologize for a repeat question but my 1st post was in the wrong forum and I didn't quite get the info I was looking for. I have an 01 Burb with the 8.1L and 3.73 gears. I am considering going from the stock 265/75's to a 315/75 tire effectively giving me gearing in the 3.20 range. My driving is 60/40 highway/city with very little towing or offroad use.

1) In objective terms how much performance loss will I notice?

2) Will a true flow intake, magnaflow exhaust, and custom PCM help to make up for the gearing loss or is there no solution other than a gear change?

3) If a gear change, then to what gearing 4.10 or 4.56?

Thanks alot, Craig

oldred95
01-04-2005, 01:16 PM
I doubt you would notice too much loss with that big of an engine. If it were me I would go with exhaust and intake. Those two along with the higher gear ratio will really help out your highway mpg's and probably not affect city mpg's all that much either.

smokshwn
01-13-2005, 04:33 PM
Come on guys throw me a bone here. Am I in the wrong forum? I know there is more than one opinion on this floating out there.

Thanx again Craig

mudpuppy
01-13-2005, 05:26 PM
I would suggest not so radical of a tire. You dont want to regear to 4.10s.

The truck I am looking at to upgrad too has a 8.1/allision/4.10 which Im thinking that I will have to use at least a 33" tire to get use of the gear ratio.