Skip the auto shop - Our mechanics make house calls

Q: Transmission locked

asked by on

Removed engine while waiting for replacement I was pushing truck in and out of shop until eventually one day trans locked up. I removed drive shaft to push truck in and out of shop. I have received new engine and installed it but need to line up flywheel bolts but need to unlock trans.
My car has an automatic transmission.

A: For your GMC C1500, the transmission input ...

For your GMC C1500, the transmission input shaft should still turn by spinning the torque converter. If you cannot turn the converter, then you are binding the engine and transmission together.

What may have happened is a torque converter that may have slipped part way out of the transmission and started binding the front pump. You will need to remove the engine out of the way and remove the torque converter from the transmission to see if any damage was done to the transmission front pump or input shaft.

While supporting the front of the converter insert into the transmission by spinning it and pushing it into the transmission at the same time until it is fully seated into the transmission, and then you should be able to turn the front transmission pump by turning the converter. Install the engine and hook it up as normal. If you need help with any of this, a certified technician from YourMechanic can come check your car and advise you with this installation.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
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・Save up to 30%

Get a quote

What others are asking

Q: Intermittent stalling while idle or driving

Hello there. Many common faults can cause your 1994 C1500 to have intermittent stalling when driving. You have done well in replacing the injectors, fuel pump, and other sensors as well as the plugs and wires, as these are typical...

Q: Which GM pick up rear end has posi, disc brakes and will match my 67 measurements?

Hi there. The axle from a 2001 Chevrolet Camaro should fit your 67 GMC. The axle is about the width of your original axle and it has disc brakes with the posi loc traction control in the differential. If you...

Q: No start

Hello. The symptoms you describe can be caused by a few different things. If you have already replaced those components then the next things I would look at are the starter relay, and the vehicle's battery and ground cables. There...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.