No Forward or Reverse. Transmission Toast?

[BanditGTP]

Hi guys. I can't seem to catch a break. I've been putting some miles on my truck (03 GMC Envoy XL) again after a few past problems and while driving around 30-40 mph, I got on an entrance ramp onto the parkway and when I stepped on the accelerator, it felt like I was in neutral. I stepped harder on the gas and the RPMs went up but I was just coasting. I pulled to the side of the road and sure enough, I had no forward or reverse anymore. I could shift through all (RND321) and wasn't getting anything. I checked the fluid and it was full and did not look burnt (I just changed it recently). When I shift into Park, it still locks the truck in place so it doesn't roll.

I know when my transmission started to go on a previous car, I started to lose a gear here and there. Not the entire kit and kaboodle like I have now. I didn't hear any loud noises and no grinding. I've read about the fluid pump going bad. Please correct me if I'm wrong, but if I disconnect the transmission line from the radiator and start the engine, fluid should be pumping out. If it doesn't, that would be a indicator that it could be the pump. Correct? ...and in order to replace the pump, the transmission would need to be dropped.

Thanks for any help or suggestions.

 

[Blckshdw]

When my transmission ate itself almost a year ago, I had the exact same issue. Heavy traffic jam of crawling traffic on the interstate, when it started to clear up, I stepped on the gas and the truck just coasted under high RPMs. Got to the shoulder, and had no forward or reverse. Turns out my clutches had eaten themselves, and there was metal found in the pan. Ended up getting a replacement since I wasn't near home.

 

[BanditGTP]

Thanks Blckshdw..I guess I'm going to test the pump situation like I mentioned and then possibly drop the pan to see if there's pieces in there. Now I just need to wait for a nicer day since I've come up with Coronavirus projects to keep me busy in my garage which means I have no room for the truck. I guess I'll be doing this in my driveway. Hopefully I can do this without making too much of a mess. If the pump is actually working then I can use that to drain the majority of the fluid from the pan and hopefully keep the mess to a minimum.

 

[Mooseman]

There have been a few that came here like you and pretty much all of them their tranny was toast. It could be the pump but in either case, you'll have to drop the tranny.

 

[BanditGTP]

Thanks. That’s what I was afraid of. By any chance do you know if it’s possible to drop the tranny without a lift? I swapped out the tranny on my 04 Grand Prix in my garage without a lift. I dropped it out the bottom. I really don’t think I want to go this route though and also don’t think my wife will appreciate it if I took it to a shop and spend a ton of $$$ to get it repaired. With 347k miles on it, it might be time for it to go😥.

 

[BrianF]

I'm no transmission specialist but start with the easy things. check to see if the pump is working by disconnecting the coolant output line and start the engine. If your pump works then pump the pan dry to drop it for inspection. You can get a good look at the fluid as well, see how burnt it may or may not be. Maybe it's as simple as the fluid is low or filter was never seated properly. That and see what debris may be sitting on the pan.

Good luck though!

 

[Mooseman]

You can certainly swap it yourself. Just the transfer case to deal with but other than that, it's pretty straight forward. The two top bolts can be accessed using really long extensions.

Putting in a used one is a total crapshoot if it will be good or not or will last. Just open it up first to be sure the fluid in the pan looks decent and there's no junk. A yard's warranty won't cover your labour if you have to rip it out again. The overall condition of the truck should dictate if it's worth it.

 

[BanditGTP]

I had a chance today to test the pump using the transmission line to see if the fluid was circulating. Unfortunately no significant amount was draining out. I just did this same procedure recently when I changed the fluid and filter so I know how much should be coming out and it wasn't the same as last time.

Mooseman... I wish I had the help because I might try it since I have extra time on my hands now due to the "social distancing" and lack of work . I may still try to drop the panto see what may have happened but I'm almost afraid to say that the time has come...Time for a new truck😢.

 

[Reprise]

I just did this same procedure recently when I changed the fluid and filter so I know how much should be coming out and it wasn't the same as last time.

You did get the 'deep pan filter', right? If the 'short' one is used in a deep pan, it will fall out of the pump feed orifice (and then the pump gets starved).

Since you replaced the filter, you'd probably have noticed if the snout on the new filter was appreciably shorter than the old one (by about 2" or so). But I figured I'd ask, given that you did the work recently.

I'd pull the pan at this point, to see what you find. You've done it before, so you know what you're in for. Might as well see for yourself before scrapping it (yeah, I think it's toast, too).