Power Loss

[PekingMan]

Recently I purchased a new set of BFG 31" tires. My explorer has the stock gears of 3.73 (with Automatic tranny), which I thought would work really well with the tires based on what others on this site use. However, I have noticed a very significant drop in power which I don't understand because my friend's explorer (same year) has 3.27 gears (with manual tranny) and stock tires and seems to be much faster than mine. I'm really confused because while the 31" are bigger than stock, I didn't think it would bog down my explorer as much as it has. I know manuals are quicker but I am really confused as to how an explorer with 3.27 gears is that much quicker. My other concern is whether or not is it worth installing 4.10 gears. Is there that much of a difference between 3.73 and 4.10 gears? Would my money be better spend by possibly cleaning the MAF and installing a KKM filter charger, exhaust, headers, etc.?

 

[Henry]

Chris,

I have also recently installed BFG 31" tires and have the 3.73LS diff. with auto transmission; however, I have not noticed any power loss.

Sorry I can't give any pointers, but it shouldn't have hurt your performance much at all.

 

[Goober]

Hey PekingMan, I can't see how you lost so much power either. I suffered from the 32, but not that bad. I have 3.73's and was thinking about putting in 4.10's to make up for the difference. I do a lot of highway driving and just aren't sure they would make that much difference. Putting in the Splitfire wires, +4's and K&N filter seemed to help quite a bit, but I understand about the off-the-line loss.

The main difference I see from the gears is the ratio of the 4.10 would get you closer to the original rpm level. This would help out on mileage, but not sure if it will make a heap of difference in off-line performance. Perhaps someone who has mastered the art of gear swapping will shed more light upon this subject.