2003 GMC Sierra 2500 - Transmission?

[dad911]

tl;dr - heavy load backing up, now trans has no reverse.....

So I was backing a loaded trailer (about 8000#, open trailer with a mini-excavator) up a driveway, sloped but not terribly steep. Reverse went out. Dash display flashed something like 'Transmission Overheat' but I didn't see while backing, head turned. Note: 12,000# towing capacity, just under 100k miles.

Also was a shudder at some point backing, I thought it was because I was in 2WD, so switched to 4wd.

Now truck drives forward, no reverse.

Swap in a rebuilt? Can I drive if in forward(to shop), or is that likely to go soon?

[yetibone]

Drive as far as it'll take you towards where you plan to repair it, or have it repaired. Tow bill will only get smaller the farther you go.

Strange that it only lost reverse.

Edit: might be an electronic problem since the hot fluid warning came up on the DIC, or valve body problem. 4L80E is a pretty tough transmission mechanically.

[dad911]

Originally Posted by yetibone

Drive as far as it'll take you towards where you plan to repair it, or have it repaired. Tow bill will only get smaller the farther you go.

Strange that it only lost reverse.

Edit: might be an electronic problem since the hot fluid warning came up on the DIC, or valve body problem. 4L80E is a pretty tough transmission mechanically.

It was in Reverse when I was backing up driveway, loaded.

[Oh Haha]

Did a Google search on the problem and it looks like it may be repairable by you.

At least worth looking into the servo.

http://www.fullsizechevy.com/forum/general-discussion/technical-maintenance/487755-4l80e-no-reverse.html