Allison transmission question

[Lynn1130]

I am not sure you even need to drop the pan. I think you get about the same amount out by changing the filter (and moving the magnet) and pulling the plug to drain. It takes right at 6 quarts as I recall. It is a little more expensive but I changed the fluid and filter, drove it about 2K miles and changed it again. That pretty well removed the old and gets a good level of new in. TorqDrive (Amsoil ATF) is more expensive but considering I plan on driving this truck for awhile cost is not an issue.

If it ends up being a problem that has to be repaired in shop I would then ask them to use synthetic as the replacement fluid.

 

[porthole]

Dropping the pan and changing the internal filter.

Although I don't advocate it for the DIY'r, loosening the valve body will allow some oil to siphon out of the converter. Enough to make it worth while? Don't know, but it was a common practice when I did a lot of trans work.
And, dropping the pan gives you the opportunity to replace it with a deep pan.
Probably don't need the deep pan either, but for me, I like having the volume.

 

[GMCaddic]

2008 HD diesel with Allison. Has been almost perfect since we bought it new.

May not be a factor but we are now up in colder weather than we normally see. A few days ago for the first time check engine light comes on. And it will not shift out of 1st gear. It was in the 20's outside. Went to auto parts store and the error was something about low pressure.

We we cleared the alarm and all was well

same thing happened 3 days in a row but I realized my chip programmer would clear alarm. I would start the truck get the check engine light shut it off immediately then clear the alarm and all was well.

This morning in KY (we left rig in Nashville) no check engine but when I put in to gear to back out the truck moved a foot then seemed to start to coast. Engine was still running but no transmission

i looked at at the DIC and it said "transmission disabled put in neutral to reset". I had to do that about 10 times in order to get in front of the motel to load up the luggage.

Let the the truck run for that 5 minute period to load up and drove off like nothing was wrong.

Any ideas? What am I up against here or cost to fix if you had the same problem

or what site out their might be better?

I did check TRANS fluid and it might be a little low but well within limits.

Thanks

HEY Gary just wondering if you got issue resolved with your transmission?

 

[Garypowell]

Thanks all!

I am now in upper Alabama and have not had any more problems since warmer weather. I think like some have suggested it is probably electronic or sensor. But until it fails 100% I'll leave it alone.

I tried the duramax site but no help there.

I'll write again if it fails and what it takes.

 

[porthole]

Can you check your cooler lines to make sure nothing has damaged or put a crimp in them?
Do your lines have the rubber hose connectors? Can you feel them to see if they are soft?