3L80 Tranny issues

[badgerord]

Looking for some insight from the mind hive.
My 1986 M1044A1 HMMWV was running great, took a 30 mile road trip to visit a buddy that just bought a new plane. As I approached the airfield I had to stop at an intersection, when I pulled away from the line had no 3rd gear (3L80 Tranny) after a little bit it popped into 3rd, but at the next stop, it would not go into 3rd at all, than after another 2 miles, no 2nd gear.
Checked it for Vampire syndrome, nothing, checked fluid level, it was OK. Any ideas???

 

[rcamacho]

Likely an internal failure. Probably prudent to drop the transmission and inspect/rebuild accordingly


Sent from my iPhone using Tapatalk

 

[NDT]

Worth it to check the modulator function and governor gear condition, both can be done with the Hydramatic in the truck.

 

[badgerord]

Well it turns out there is a bunch of Aluminum in the pan, need a new tranny.
Who has reputable rebuilds ???

 

[NDT]

Personally I would find a highly rated local transmission shop and have them do a “ bench job”.

 

[Maxjeep1]

So you could have aluminum all thru the lines and cooler, torque converter? I had a transmission go bad under warranty and fixed by the dealer and I didn’t make it out of the parking lot before the new transmission failed because they didn’t replace torque converter that was full of shavings. Does transmission share fluid with the transfer case? What a mess

 

[badgerord]

So you could have aluminum all thru the lines and cooler, torque converter? I had a transmission go bad under warranty and fixed by the dealer and I didn’t make it out of the parking lot before the new transmission failed because they didn’t replace torque converter that was full of shavings. Does transmission share fluid with the transfer case? What a mess

Yes it does, and a cooler !

 

[Action]

Yes it does, and a cooler !

The transfer case has a fill plug. The transmission gets filled through the dipstick tube. The fluid inside of each does not mix.

 

[osteo16]

The transfer case has a fill plug. The transmission gets filled through the dipstick tube. The fluid inside of each does not mix.

Unless it goes through the vent

 

[Action]

Unless it goes through the vent

Or busted cooling loop !

 

[Ajax MD]

Well it turns out there is a bunch of Aluminum in the pan, need a new tranny.
Who has reputable rebuilds ???

I see these transmissions for sale all the time because people are always upgrading to the 4-speed. Normally I'd be skeptical of buying a used automatic transmission but the 3L80 is so robust that I think the risk is acceptable.

Why not ask around for a used 3L80 and see how it prices out compared to a rebuild?

 

[Mogman]

Heck I have one with 6K on it but I am in Texas, no doubt you can find one much closer.
The transmission cooler is a multi pass and they are very difficult to get clean, I would suggest replacing it.

 

[kzeyus]

Just pulled a working 3l80e and 218 xfer out this past week to replace with 4l80e. I'm near Rogers, AR about 4 hours south of KC