TheEvilBain_TDB

I have a 2002 Convertible GT (Dont knwo if this matters but it has the Traction control as well). Already it has underdrive pullies and 3 inch straight pipes with Magnaflow Mufflers (no cats). I notice first gear is kinda slow and Im sure I have the stock gears in it. At 60mph in 5th gear Im turning around 1,700 to 1,800 RPM. I was woundering if I switched my rear end gears out what is the best all around gears? I do still want decent gas mpg. I drive 20miles one way to work but still would like alot more off the line. Ive heard 3.73 and they dont really hurt MPG and Ive also heard 4.10s would be to much and probably better for a automatic. Thank you for your time Im planning to buy some gears this next week.

ddmsgtr1

I can tell you my 4.10's really haven't hurt my MPG much at all, and definitely gave my car the kick it needed. It depends on your overall goals though. Just a nice bolt on NA car, 4.10s are where its at. Blower, I'd go 3.73's. If you plan on turbo later, I don't know if I'd go higher than 3.55's. It all depends on what you're looking for, but in current state 4.10's will do you fine.

Rockwell28

went with 3.73 my mpg in the city seems to be a little better but it only went down like 2mpg on the highway. thats a happy medium for me if i did str8 city driving, dragstrip and hardly any highway then i would love to have the 4.10 but for a mixture of driving and only hitting the track about 6 times out of the year i love the 3.73 and wouldnt trade them for anything

TheEvilBain_TDB

I do plan on a blower someday but Im looking to get another 4.6l that has bad rings or something to start building up. My car right now has 142,000 miles on it but dosnt use anyfluids at all. So maybe for now 4.10s would be fine I might lean to the 3.73s I guess I just dont know what is best for my car and my situation lol. WIth 4.10s is first pretty much useless? Another thing that is bothering me is that it shifts great but when I really get on it it grinds before going into second. Im hoping its just the clutch or adjustment or something. I hope its not a bad syncro.

uberstang1

More often than not thats a sign of a synco issue.

TheEvilBain_TDB

Thats what I was thinking.

devongarver

Usually if its the syncros won't it still be rough/make noise even when you are easy on it shifting gears? I would think clutch cable is stretched or needs adjusted.

cliffyk

You need to drain and refill the transmission, and use only 3.2gts of fluid per this TSB.

I had used Royal Purple Synchromax for 60k miles or so, but have since found Mobil 1 ATF to provide much smoother shifting...

As to gears, I specifically chose 3.73s because I do a lot of driving on the Interstates. They initially cost me 0.5mpg or so overall, however I made that up that and then some by tweaking the tune.

TheEvilBain_TDB

Thank you for all your help. I did notice when I get on it if I leave the clutch in for a extra second or two it wont grind only when when I speed shift it will grind. Dosnt make any noise during normal driving. Im going to drain the tranny this week. I do think Im going with 3.73s since I cruise at 60 to 65 two times a day 20miles each way.

mrtstang

There's always 3.90's.