What is the stock set of rear end gears that come in a new modular mustang GT?? i think the person i bought the car from said he put ford racing 373 gears or something...and i had to wire in a Brother performance speed calibrator because the speedometer was reading 5 or 10 mph more than it was....
what set of gears does a stock 1999 mustang GT come with
matrixman
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What is the stock set of rear end gears that come in a new modular mustang GT?? i think the person i bought the car from said he put ford racing 373 gears or something...and i had to wire in a Brother performance speed calibrator because the speedometer was reading 5 or 10 mph more than it was....
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and the 3.73 would obviously make the car wind out easier on the highway?? also i got the car with 26,000 miles so is there any way to find out how many miles the car really has? as im sure the move from the 3.27 to 3.73 added more miles than the car was really running...
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Well no it was not...i did it a few months after i bought it after i found that speed scanners were saying i was going 10mph while the car said i was going 5mph....and i dont know how long the guy had the gears installed and was driving the car like that....how many more miles could have possibly been added? because after i put the speed re calibrater in the speed matched what the radar was saying so it worked
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is that your car on your posts? a lazer red gT?
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Redfire, yes. 2003 they changed it to Redfire. It is seriously the slightest difference in color from Laser Red though.
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No way to really tell w/o knowing exactly what miles the gears were installed at. Best bet is to do this....Use a gps, clear your odometer, drive a mile on the odomoter, look at the gps, see how far youve driven. Calculate what the car is racking up on the odo per actual mile. Do the math for however many miles the car has. You know thats how many miles it has at the very most/least depending on if its reading higher/lower than actual.
Example:
Car reads 1.25 mile per actual 1 mile
Odometer currently reads 10k miles
10000*.25 = 2500
10000-2500 = 7500
So it has no less than 7500 and no more than 10000.
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Yeah..well the car as of now has almost 35,000 original miles so thats low for a 1999 anyway...as long as i know that it actually has even lower miles is good to know...lol..when i bought it it was sitting in a heated garage on top of a carpet so it would pull any moisture away from the car so its in showroom condition...lol...
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It's also possible the previous owner had a tuner which calibrated the speedo. When he sold it, they could have removed the tune and now the calibration is off. Worse case scenario, you've got slightly higher mileage. Once you find out how much the speedo is off in percentage, multiple your current mileage by 100% - your estimated percentage the vehicle is off and you have an idea. (ie, if you calculate the speedo is off by 3%, multiply your current mileage by 97% and that is your estimated mileage.
On a funny note, you could get a tuner and change the gearing to be higher than you truely have making the speedo slower by 5 - 10 MPH and reverse the effect. LOL
Good luck bro!
On a funny note, you could get a tuner and change the gearing to be higher than you truely have making the speedo slower by 5 - 10 MPH and reverse the effect. LOL
Good luck bro!
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yeah thats an idea...lol...thanks
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I believe that's the wrong way. 3.73 gears mean that the driveshaft (and the transmission) spins 14% faster than with 3.27 gears. That would make the speedometer read faster than the actual speed, not lower. There is an easy way to check gears. Put the car in neutral and jack the rear wheels off the ground. Mark the driveshaft and the wheel. Turn the wheel one complete revolution and count the number of times the driveshaft turns. 3 3/4 turns is 3.73 gears. 3.1/4 turns is stock 3.27s.
What size tires are you running? Oversize tires would cause the speedometer to read slow.
Do you have an aftermarket gauge overlay? I thought the previous owner had installed 3.73 gears in my car. When I did the test above, I confirmed I had 3.27 gears. He had put the needle back on the speedometer in the wrong place. But that still caused the speedometer to read fast not slow. I thought I was running 60 in a 55 zone when in fact I was running 52. Its an odd feeling to have everyone in the world passing you when you think you're speeding.
Edit: When my tuner set the computer to 3.73 gears my speedometer was mostly correct but my odometer started reading slow by 14%. It took me about 6 months to figure out the needle was in the wrong place.
I used the dealer test function in the odometer to compare speedometer gauge speed with what the computer actually was reading. To get to that function press and hold the odometer reset button and turn on the key but do not start the motor. When the odometer starts going through its test sequence release the button. When its finished testing itself press the button until the odometer reads eng00000. That stands for English measuring systems (miles per hour). Start the engine and drive the car. Your odometer is now a digital speedometer. When you shut off the car the odometer will reset to its normal function.
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Very cool info...but the car came with the stock gauge cluster witch was reading faster than the car was going,and when i installed my Auto meter lunar series gauge set it was reading exactly the same...so once i installed the Brother performance speed calibrator everything adjusted properly...the car was also reading the wrong miles driven when i would set my gauge cluster to read the miles i drove to a measured location my other car that was stock and my fathers truck measured the same distance while my mustang before the speed calibrator was installed readr that the car drove further so two other stock vehicles read the same number and my stang read that it went farther....
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