[demitristewart]

Yesterday my buddy and I picked up a 1972 mustang grande that suppossedly has a transmission issue.

Here is the problem.
When you start the car it idles fine. When you rev the car up, it starts to studder. The guy that we bought the mustang from said it is the torque converter not allowing the motor to rev up cause it is sticking or something along the lines of that. I figured if the engine had low compression that it would not have idles so nicely.

Does this make any sence to anyone? I am going to do a compression test today on all the cylinders.

[Jmark]

Easiest way to check it is to jack up the car and un-bolt the converter and slide it back some, then start it up and see what happens. Its possible that the pump came apart and is locking up the converter, or it could be fuel problems. Lots of possible causes.

[demitristewart]

The engine has good compression, between 123-127 a cyl.

How do I check if the tranny is a C4 or a C6?

thanks

[HotCTruck]

I bought it from some guy and it had a vinyl top that made the car look like it had a receeding hairline, so I took it off and welded up all the holes.

My engine shudders also and has no power. I was told the engine mounts needed to be changed and that is why it does that. I have yet to check them. That sucker sure is a gas hog!

I'm selling that sucker as soon as I get my truck running!

[KULTULZ]

Originally Posted by demitristewart

How do I check if the tranny is a C4 or a C6?

• FMX- Will have a cast iron main case.
  
  
• C4- will have an aluminum main case.
  
  
• C6- will have a one piece aluminum bell and case.

If you find an assembly tag hanging off a servo, post it and I can cross it for you.

[KULTULZ]

Originally Posted by Jmark

Easiest way to check it is to jack up the car and un-bolt the converter and slide it back some, then start it up and see what happens.

I think it would best to move the convertor and transmission back a few inches on a tranny jack. If you were able to push the convertor in, it just may be drawn out again and hit the flexplate.