Which parts fail
Components named in complaints (automatic and manual transmissions, CVT, axles, driveshaft, 4WD/AWD).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 1999 Ford Mustang owners, lightly cleaned up (personal details are redacted by NHTSA).
Pre-accident conditions: daylight, raining, car stopped at red light. A few minutes prior to arriving at the red light the driver's power seat moved all the way forward completly on its own accord after stopping at the red light I re-adjusted the driver's seat and when the light turned green I proceeded making a right turn in my normal "old lady" fashion. About 3/4 through the 90 degree turn the rear wheels lost traction and began to slide to the left. I immediately hit the brake and turned the wheel to the left. (I suppose it is possible that I accidently hit the cruise control button located on the wheel at this time). Anyway the car engine contiued to rev and the rear wheels continued to spin, driving me into a complete 360 degree turn, all the time with my food hard on the brake pedal. …
Swe purchased our 1999 Ford Mustang gt new and a 25K miles yhe rear end differential was making a lot of noise. Ford replaced the entire third member unit and all carrier bearings. At 35K miles the issue reoccued and this time we took the car to a diiferential specialist who said the carrier bearings on one side were completely gone and replaced them. Then at 45K miles the seme issue developed and we took it back to the differential expert. He could not ubderstand the failuer and upon further analysis determined the the differential housing was bent and his view was that ist was manufactured that way or it bent I=on the delivery ride to the dealership. The diff housing was professionally straigtened and now the car has 95K miles on it and no further problem. We wrote Ford about this and never receieved a reply.
I had a hard time shifting so I brought it in for a check and an independent service found this wrong: input shaft retainer...I also need my clutch replaced because of the damage caused by this. My car only had around 25,000 miles on it at the time. The service person told me that this part was installed wrong and human error caused the problem. My bill was $751.12 and I contacted Ford about this and they told me basically tough luck. There is no way a transmission should go bad at 25,000 miles. Can you look into this for me? I still have the bad part and you can see the damage that was made to this part. Thanks
Vehicle is 1999 Ford Mustang, 3.8 liter engine with 5-speed manual transmission. Dealer replaced clutch,throwout bearing and pressure plate at approx. 2000 miles for original owner. Dealer did same work for myself (2nd owner) at approx. 20,000 miles. Car now has 54000 miles and clutch work is again needed. I have owned many fords with manual transmissions and never had a clutch last less than 100,000 miles, so my driving style can't be the problem.
While driving and stepping on brakes pedal brakes will not work properly. Also, while vehicle was parked with first gear (manual trans.) and with emergency brakes on , transmission jumped out of gear, but brakes did not hold, and vehicle rolled back, crashing.
While vehicle was in park and running consumer was outside of car, walked down driveway to open gate and consumer heard a pop, and vehicle started to roll down parking lot. Consumer had to dive inside to set emergency brake.
Rear end has failed on vehicle two times within 4 years. After 1 year, begin to hear a grinding sound coming from the rear end. The second incident, I heard a scrubbing sound coming from the rear end.
25,000 miles on 1999 Ford Mustang 5-speed difficultly shifting into reverse - pilot bushing defective - transmission needs to be pulled & repaired - very costly 3 yr warranty expired 4 mos. Ago .
Car stalls out while in motion. Has happened turning a corner, on a bumpy road (2" road construction drop off), and for no apparant reason. Does not happen very often, but can be very dangerous if in heavy traffic. 2) when trying to put car in reverse while stopped (coming out of my garage or a parking space, for example) gear shift refuses to go into reverse. Putting into first does not help. I have found that letting up on the clutch just the right amount will usually let it go into reverse. 3) seatbelts are much to sensitive. Just driving down the road you can hear them repeatedly clicking, locking and unlocking. You have to make any movement very slowly or else you will be snapped back to the seat. Turning to look over your shoulder at traffic will get you locked in. Extremely dangerous. …
This is the third pressure plate replacement that has been put into this car. I now have a one of a kind hand built pressure plate because the factory could not find a plate that fell within the factory tolerances. During the current time at the dealership ( approximately 3 1/2 weeks now) the dealer could not get the car into gear and stated that the shifting forks were probably bent anf not letting the car shift plus the pressure plate issue.
Transmission complaints in other Mustang years
Frequently asked questions
How common are transmission problems on the 1999 Ford Mustang?
NHTSA has 30 complaints about the transmission & drivetrain of the 1999 Ford Mustang, 12% of the model year's 258 complaints. The component named most often is automatic transmission (11 mentions).
Is there a recall for 1999 Ford Mustang transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 1999 Ford Mustang, though it has 3 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 1999 Ford Mustang transmission problems start?
Half of the complaints with a recorded mileage happened before about 35,000 miles, and 14% before 25,000 miles.
Is it dangerous?
Owners linked 3 crashes, 0 fires and 0 injuries to transmission & drivetrain problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.