I have a 2005 Chevrolet express g3500, cargo van,great vehicle engine has 420,000miles,yet still in pristine condition,but the van has run through 2 transmission changes,the third transmission just failed. Doesn't enter the parking gear, doesn't reverse,only moves when you put it on 3.
my question is has anyone ever attempted to fix a failed transmission system? Was it worth it? Finally how do I prevent a future transmission issue?

 

Is this the 4l60e or 4l80e? impossible to say why it failed without an expert tear down.

However, I’m a fan of shift recalibration kits. If you haven’t had one installed, you might consider one. Transgo and Sonnax both sell solutions “kits” to boost pressure, increase holding power and shorten shift times. Both companies research common failure points in your model and engineer improvements.

I put in a $30 sk4L60e kit from Transgo in a new to me 95 g2500. I’m very happy with the results. Not harsh at all but a noticeably short shift to all gears plus converter lock up.

Something to consider.

John

 

You said you went through 3 transmissions. Were they new, rebuilt or used? Do you do a lot of towing?