Auto help needed

[wcjp]

Just received an email from a friend. His rig is a 99 3/4ton CTD auto 4x4. The CTD has a Superchip, 4" exhaust and air intake. I won't talk with him until tomorrow. He says at 3000rpms he can achieve 10mph with no boost. Is the Auto toast? The truck has about 45,000miles. Any tips or troubleshooting ideas accepted. I have a manual. I view autos as black magic.

 

[wcjp]

I was wrong before. It'll make 20lb boost. The wife was driving at the time. She pulled upto a stop sign. When she tried to leave the problems began. In 1st or Reverse it runs fine. When in drive the truck has a real problem trying to go. I talked with him earlier. He pulled the APPS to clean it. Beyond that I don't know anything about Auto's.

 

[rrausch]

It's probably more serious than this, but if your friend hasn't checked the fluid he should do so. Check it while the engine/trans is hot, park on a level place and cycle through the gears, PRND21 ending up in Neutral with the emergency brake on, engine running. Fluid should show a little high on the dipstick--if it reads a little low put some more in, if it looks or smells burned change it along with the filter.

 

[Philip]

If he has a good 1st and reverse. Sounds like the main drive clutch pack has went bad or something in the hyd circuit has failed.



If he has a FSM he needs to run some pressure tests on the trans.

 

[wcjp]

The owner just brought the truck home. It was an easy fix. The speed output sensor failed.

 

[rrausch]

That's gotta be good news!

 

[Chipstien]

And I was gonna say it sounded like a 3rd gear start.