Q: I changed the gearbox but the car is only moving in reverse and it needs acceleration up to 6000rpm to reach 30mph.

asked by on November 05, 2016

I was having harsh shifts with my old gearbox it was not engaged in reverse at all,so i bought a second hand one. This one have very smooth reverse but on D it will move only 25kmph even if the engine is at it maximum i.e.8k rpm. Is the gearbox not good or is there any sensor problems. Plz help.

My car has 140000 miles.
My car has an automatic transmission.

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

How do you send numbers or names during a call with the HandsFreeLink?
If you need to send numbers or names, for instance if you’re trying to navigate a menu on the phone, you can do so with the HandsFreeLink® (HFL) system pretty easily. Here’s what you need to know. Press the talk...
Gas gauge not working properly.
I would have a technician check the codes on the computer (https://www.yourmechanic.com/services/check-engine-light-is-on-inspection). It may help find the problem your having. The gas gauge not working could be the sending unit in the tank or the wiring going to the gauge....
Cassette player not working
If the cassette player does not play, then get a cassette cleaner and try cleaning it first. If this does not work, then the radio will need to be sent out for repair, or the radio would need to be...
Whining noise while releasing the throttle
Whining noise is almost always caused by some kind of a bearing problem. So you might get a stethoscope or get somebody to listen. Jack it up in the air and stick it inside and listen to the throw out...
Infotainment system freezing up
A few different fault can cause the screen to lock up like this. The most common would be the touch screen failing, the info system failure, or the radio itself. Since your car is still fairly new, you may want...
Why won't my van crank?
Look at your dash when you turn on the key to see if the theft light is on. If it is, then you have a problem where the theft system is not deactivating. Try to get out and lock all...
My Yukon Denali is AWD. With front tires off the ground, should the drive shaft and both tires spin freely of each other?
Hi there, thanks for writing in. I'd be happy to help. This is a normal thing. Your front axle carrier has an electronic actuator that locks it in only when the transfer case is locked into 4WD. The fact that...
car overheating 225
Normal engine operating temperature is up to 225 degrees. As long as you are not over that value, the engine is not overheating. Intermittent cabin heat means there is an obstruction in the coolant flow and that obstruction can be...
When I shift from drive to reverse or vice versa it makes a clunking noise. 1997 Land Rover Discovery
Hi there - the clunking noise you hear from shifting forward-to-reverse (or vv), is the result of a small amount of wear and loose motion in the driveline. This could be a worn u-joint (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-universal-joint-u-joint), differential gears, or splined coupling...

Related articles

Understanding Main Gears Vs. Planetary Gears
Aspiring Aspiring mechanics spend hours learning about how main gears and planetary gears work in a car transmission, so a full dissertation simply isn’t possible within this relatively brief article. If you’re curious about how they work, though, this brief...
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.
The Mechanics of Cars: Simple Machines in Automobiles
Simple Simple machines are single, mechanical devices that help improve the daily life of humans by allowing them to work faster, easier, and more efficiently. Simple machines are considered to be the basic mechanisms that all complex machines...