98 Speedometer Recalibration Gears?

Mustang414 · **98 Speedometer Recalibration Gears?**

I just put 3.73's and t-lock in my car and now my speedometer is reading rather high. What gears do I buy? Where can I get them? And how do I install them? Thanks a bunch!

Zim · 06-24-2004, 04:40 PM

buy the white calibration gear... should be 23 tooth. Ford didnt have my part so i went to the dodge dealer and they had it (ford guys actually referred me over there) I guess they use the same gear in the grand cherokees... whod have known? But yeah, its white and its a 23 tooth... costs about 15 bucks if i remember right

**SpectorV** · 06-24-2004, 06:48 PM

no matter what you do you cant correct the speedometer it will alwasy be off.... unless you buy a drive gear, take the tranny out and replace the drive gear (what the speedo gear drives off of) its the only way to fix if if your car is not speed cal compatable.

Zim · 06-24-2004, 08:29 PM

with 3.73s the 23 toothe one should get it pretty close... im talkin within a few %. I know when i did mine, i have 4.10s and the 23 tooth is the best i was able to get, and im off by approximately 8-10 mph throughout the speedo range

**SpectorV** · 06-24-2004, 10:21 PM

with my 3.72 and a 23 i was 5mph off.. still to much you possibly can get a speedcal if so definatly do it. you wont need a new speedo gear just buy the speedcal and put it on, it compensates over the stock everything to correct for the new gears.

97Stallion · 06-25-2004, 12:07 AM

Since I have a 150mph speedo, I use a green 8 tooth drive gear and a 23 tooth driven gear for my set up and I have 3.45 gears and I'm dead on. I think I'm actually 0.1% off.

**SpectorV** · 06-25-2004, 04:03 PM

why do you want a 150 speedo its harder to read

97Stallion · 06-25-2004, 07:57 PM

It's not harder to read at all.

**SpectorV** · 06-25-2004, 08:46 PM

still why would you want a 150 speedo other than to be like a GT ? did you plug it up and it worked minus the fact that its not accurate? is the rpm gauge even accurate? i bet your speedo (odometer readings) are probably off, thats an interesting point though pre 99s are not like the 99 ups whos odoemter is not on the dash its stored in the computer.

97Stallion · 06-26-2004, 12:39 AM

No my car is 99.99% correct. And it doesn't work like the way you mentioned. The calibrations for the speedo are inside the cluster itself, but it reads with a different drive gear. Stock V6 mustangs are a yellow 7 tooth gear, GT's have a green 8 tooth drive gear. 94-98 guys need to use a 94-95 gauge cluster so that the rpms are correct, on the 96+ GT's the RPMs go up to 8000, but the 94-95 ones go up to 7000 like our cars. Don't you go past 120mph on a regular basis?

**SpectorV** · 06-26-2004, 02:00 PM

yea your right the reading would be the same cuz its dependent upon the speedo reading. just odd to go though all that trouble for a GT gauge setup. Ive never cut off my car and its rather stupid to go past 120mph.... and stock they cut off at 115 anyway. Its very dangerous to do that and no point in it the car also feels very unstable at those speeds lol.

97Stallion · 06-26-2004, 07:14 PM


Quote: Originally Posted by SpectorV yea your right the reading would be the same cuz its dependent upon the speedo reading. just odd to go though all that trouble for a GT gauge setup. Ive never cut off my car and its rather stupid to go past 120mph.... and stock they cut off at 115 anyway. Its very dangerous to do that and no point in it the car also feels very unstable at those speeds lol.

It was no trouble at all.

maverik · 06-27-2004, 08:48 PM

SPEED CAL SPEED CAL SPEED CAL... you guys can argue over the gears and how much you are off blah blah blah, but... coming form a person with 4.10 gears and t-lok with a speed cal on my automatic 98 I can personally vouch that this puts the speedo DEAD on. I had a buddy in a ls1 unmodified vette cruise next to me all the way up from 10 mph-117 mph before my car wouldnt go any faster and every step of the way it was a perfect reading. So... food for thought.
Dan