Allison transmission sprung a leak. Anyone else?

BurbMan, I seem to recall a thread you had going last year where you had your TT on and stuck across a CG road.....

I appreciate the info from everyone.
I will check out the aftermarket cooling line fixes too.
I am a member on the diesel place so I'll wander in there too and do some digging on the subject. Good suggestion!

I have no intention of selling or trading the truck. It is in excellent condition, especially considering it is a work truck. I take care of it.

It is paid for in full and does not owe me a dime. Service over the past 7 1/2 years has been virtually flawless. Just a couple minor things, like the check engine light last summer while towing.

The shop confirmed today by using diagnostic tools to look inside the bell housing that the pump is leaking out the seal and gasket, and also the torque converter seal is leaking, and possibly the housing bolts on the converter. (don't see how those can leak)

I have known for several years that the cooler lines are leaking. It was not a big urgent thing to fix them.

One thing that concerned me was the tech guy at the stealership talked to me as if I knew nothing at all about vehicles.

He tried to convince me that changing the offending seals would now increase the pressure to all the other seals and gaskets, thus increasing the risk of failure of the other seals. I told him to his face that his statement was absolute BS and that what he told me was not true.

Should have seen the look on his face when I called him on his BS story to try to scare me into doing more than what is necessary. He said oh well you don't have to believe me. I replied I don't and that there will not be an ounce more pressure on the trans because of a new seal.

Now if the oil was spurting out like a garden hose, then yes there would be more pressure after the repair, but no more than there was before on the rest of the seals.

No wonder they are called stealerships!

Think I'll take it elsewhere for the repair when I get it done.

And at the first place I had it looked at, the ex-GM dealer that is very honest, they took me out and showed me where it was dripping out the bottom of the bell housing, so I do know that is where the oil is coming out. And it was all over the skid plate too.

you Said the leak is on the front of the truck (right)?
Allison trans line are known to fail. there are a couple of aftermarket fixes. I used an aftermarket kit to replace all three hoses on my 2006 truck. about $200 and two hours of work. the hoses weren't leaking real bad but the fluid would collect on the plastic skid plate on the front of the truck and then start to drip. most of it was leaking just behind radiator on the passenger side.
I also had a leak where the yoke slides into the transfer case. it flung trans fluid all over the place. that was a cheap fix also ($10). never pulled trans or spent much money. been dry for over a year.

LOL tell me about it!!!!

I agree you maybe able to nurse it along,but there is risk involved with using the limp along approach. You will be reluctant to use the truck to its fullest. You will have to deal with the can I make it /what if worries.
Nursing the truck along will buy you some time. However in the end if the truck is in decent shape otherwise,I think you need to prepare financially,emotionally and logistically for an upcoming transmission job!
While I understand we are talking substantial dollars I can't see dumping a decent truck over the transmission.
Now that you are aware of the issue you have time to adjust and prepare. Use the time accordingly, We don't always get a warning call. Sometimes things just break on the spot without warning!

AYRTIME wrote:
Check in with the guys on Diesel Place Forum.
www.dieselplace.com/forum/
Check for "Pump Rub", a common problem.

Pump rub is a transfer case problem. IIRC it was corrected on the 6 speed version. If not, Merchant Automotive has a complete repair kit for $99.
(That's not including a transfer case to replace the one with the rub hole in it).

That's what I call service! I would think long term though....just because it's dripping now doesn't mean it's going to drip for ever. At some point the leak may get worse, to the point where you can't add fluid quickly enough. I don't know if these particular seals can fail catastrophically dumping all the fluid in short order or not.

I would either sell/trade it now while it's still a minor drip, or be ready to do a rebuild if/when the time comes that the leak gets worse. It may drip forever, it may get worse next week. As was suggested, head over to diesel place and see if anybody has had the same issue and you'll know what to expect.

hard to believe they get that kind of cash for the cooler lines, I just bought OEM Delco lines for $13 each online. Still pi$$ed the shop didn't change those when they had the trans out, they are a pain to reach.

And then they charged me $240. for the privilege of giving me the estimate! :E

Good plan (IMO).

Regarding cooling lines, these are often $40 parts that require a lot of effort to snake through the crowded engine compartment. If it was me, I would make Google my friend and find out what kind of DIY fixes were floating around on the internets.