Q: Rebuilt transmission performs worse than previous one - 1990 Toyota Supra Manual

asked by on September 10, 2016

I recently had the transmission rebuilt. My car is supposed to be about 7-8 seconds per 0-60. I purchased it used and since then it had been doing about 10-14 seconds per 0-60. So after having the transmission entirely rebuilt, I expected better performance. Instead, it is now weaker than before and does 20-30 seconds in 0-60. In your professional experience, why is it running worse after the rebuilt transmission and what can I do to get my car to perform better?

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Can I customize which doors unlock with the remote or electronic key?
Your remote and/or electronic key let you lock and unlock the doors of your car, but you can actually change the default pattern for unlocking if you prefer. Here’s what you need to do: Turn the engine off. Make sure...
Humming sound when car is running
Hey there. A humming sound is a common noise made by bad wheel bearings or defective tires. A wheel bearing plays a huge role in the safety and stability of a vehicle. Being that they are such crucial components, I...
Car misfires when cold
My first recommendation would be to have the Check Engine light scanned (https://www.yourmechanic.com/services/check-engine-light-is-on-inspection) for the code it has produced to ensure that a misfire is the issue. Once the code has been pulled by qualified technician, they will be able...
Vehicle making grinding noise when turning right
This is typical of a hub bearing that needs to be replaced. The noise varies when turning in one direction because pressure is being put on the worn bearing during that turn. In extreme cases the hub and tire will...
Steering tilt not working
Hello. There are two motors for the steering column features in your 2005 BMW 745Li. It is possible that the motor for the tilt feature is faulty or that a fuse or relay has blown to prevent the power steering...
Knocking noise - 1997 Oldsmobile 98
Hi! I recommend having a close inspection of the harmonic balancer on the front of the crankshaft. When the rubber that's bonded between the pulley and the hub begins to fail and separate, it starts to move around and can...
I accidentally got synthetic oil instead of regular motor oil and only put in quart and a half. Will it mess up my engine?
Hi there. Today's synthetic oils are much different than in years past, so accidental mixing like you've described is not as damaging to the engine as in years past. However, I would recommend having the oil changed (https://www.yourmechanic.com/services/change-oil-and-filter) sooner rather...
My '65 F-100 lurches only when driven slowly.
Hi there. The symptoms that you are describing lead to the accelerator pump in the carburetor not pumping correctly at low rpm's and low speeds. Try adjusting the carburetor settings to be 100 rpm's higher and turn in the fuel...
How to replace a camshaft sensor? Shows sensor "A" on diagnostic check 2002 Saturn SL1
Hello - there is no physical camshaft position sensor on this engine. This function is handled by the coil and ignition module. The error is likely a wiring problem, either with the plug wires, or the physical wiring to the...

Related articles

How Does a Transmission Filter Work?
The The transmission plays a hugely important role in how your vehicle functions. It's connected to the rear portion of your engine and transfers power from the engine to the wheels. Without a transmission, a vehicle simply cannot move. The...
Symptoms of a Bad or Failing Clutch Cable
If your manual car's transmission is slipping out of gear or clutch pedal is hard or sinking to the floor, you may have to replace the clutch cable.
How Long Does a Shift Selector Cable Last?
When When you put your gear selector in drive, you expect to be able to move forward. When you shift to reverse, you expect the car to back up. When everything’s working right, that’s what happens. However, if there is...