How do I check what size Gears my car has?

[chalosf]

i bought a used 01 gt, automatic..it came with eibach suspension and flows so im guessing it might have gears already installed..is there a way to tell before i go and pay someone to install some?

 

[DBMSTNG]

check what rpm you cruise at in 4th gear. stock 3.27's were around 2000rpm at 70mph.

3.73's will be around 2300rpm

4.10's will be around 2500rpm.

 

[BigDave06]

You can jack the back tires off the ground and make a chalk mark on the driveshaft and attempt to count how many times it rotates as you spin the tire 1 revolution.

 

[twothousandgt]

i did the second one.. easy as hell.. driveshaft spun a little over 4 turns = 4.10s..

 

[soonerfever]

Jack the back of the car up and look at the tag on the rear axel. In the older fox body cars (87-93) the tags would tell you what ratio they were. For example you would see some numbers like 2L73 (2.73 gears) or 3L73 (3.73 gears). The L simply means locker or posi-traction. I read in a magazine that Ford usually put lower gears in automatic cars to compensate for the lower ratios that 5 speed cars had. They said that a 93 GT coupe 5 speed had 2.73 stock while the same car with a automatic had 3.55. Don't know if that it true though. I do know that the information about the tag works. If you have any problems just post the letters on your tag and I am sure someone can decifer them for you. Hope this helps.

 

[chalosf]

Cool thanks, I'm at 2100 so most likely stock.

 

[Notchbck93]

04 GT auto ... tag 3L27... 3.27:1.s and they work fine.

I am at 2300 at 70 mph in OD.