Good day guys,
I just lost reverse suddenly and quietly on my 1994 K3500 7.4 Dually. It kinda engages but does not move. The fluid and filter were changed 6 months ago. The fluid color, smell and level are good. The engine and transmission are not setting any codes either at idle or at 25 mph. I did the "run it up to 25mph in first gear" test and the result is no compression braking. I saw some reference to pins, servos, acuators, pistons? etc. on a few postings. I'm out of a job right now so a trans replacement is out of the question. What do I do now? Thanks in advance for your help. - Jeff

 

Jeff sorry to say this but it sounds like you have a broken or burnt low band. It is possible that you have an issue with a cracked servo piston however I have not seen many of these break in units that I have built. In order to check the piston you have to remove the pan and unbolt the cover for the servo. Problem here is (if memory serves me correct) you have to remove the valve body as well. The issue is couple of the bolts you can't get out because the valve body housing is in the way. Vince

 

Like Vince said... More than likely an issue with the band.

 

That sucks bud specially in your current state of employment.

Kudos to Vince for all the help and questions he has been answering for us members. We appreciate having a guru like you around

 

Does the truck have engine braking in manual low gear?