HELP our (Duramax/alison transmission getting hot

[DZLHUMMR]

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Hummer (03) H2 with an 05 Duramax/Alison 6ix speed auto. 6.6 LLY. W/9000 miles
Only owned it for three weeks. Just had Predator motorsports (who did the conversion) completely go through the whole vechical, and change all fluids etc. (SYnthetics). When I drove it home I noticed that the transmission temp.s were running much higher than "normal" About 240-250 deg. When I told the owner of predator about it he said that was pretty much normal. then today while driving 70 on flat terrain. I got the "Hot transmission" message and the temps were close to 300Deg. I stopped and I had trans mission fluid dripping from the front end of the trans. pan. I checked the level while in park at idle and it was like fife inches above the hatched area marked hot. We made it home by driving 55 and it stayed hot but over 240 at that speed.... next day checked fluid level again after warming up to 125 Deg. and fluid was 2 inches above hot hatched area. trans stayed cool around town but started to heat up again as I climbed a few hills to get home..Any help??

 

[juddski88]

i still say drop a couple qts and check it

 

[mytmousemalibu]

Ouch, Might see if its getting adaquate return flow back from the cooler, might have a section of pinched line or somthing? I'd give Mike L a call if it were me.

And Welcome to the site!:hello:

 

[DZLHUMMR]

Yes I am going to lower the fluid level today thanks. Anyone know Mike L's number?

 

[mytmousemalibu]

Inglewood Transmission Service - 714 870 7300 - Mike Lovrich owner/tech.

 

[Mike L.]

Yes I am going to lower the fluid level today thanks. Anyone know Mike L's number?

Cell # is in my sig if you need me today.

 

[DZLHUMMR]

UPDATE:
took 1.5 quarts out of trans. checked level when temp reached 175, in the hot hatched area. Drove it for 1/2 hour in hilly area trans temp got up to 200 but not hotter.

 

[paint94979]

UPDATE:
took 1.5 quarts out of trans. checked level when temp reached 175, in the hot hatched area. Drove it for 1/2 hour in hilly area trans temp got up to 200 but not hotter.

that is normal 200 for an allison.

 

[SIK LMM]

My trans temp is always 100 degrees hotter than the outside temp running a race tune and driving normal. I think 200 is too hot! Just my 2 cents

 

[paint94979]

My trans temp is always 100 degrees hotter than the outside temp running a race tune and driving normal. I think 200 is too hot! Just my 2 cents

200 too high? Are you an Allison Transmission tech? I've talked with Mike L who is and 200 degrees for the Allison is nothing. Now im not saying that if you drive around for 20 minutes at 25 mph your trans temp should be 200... but if its warm out and you cruising on the highway without the converter locked 200 is totally normal.

For the thread starter, once your trans comes to operating temperature check the level it should be 1/4 inch from the top of the hot mark.

 

[kodiak]

I have seen as high as 208 when towing heavy in the summertime. Unloaded, 180-190 in the summer.

 

[DZLHUMMR]

UPDATE: (Thanks Mike for your help)

Predator changed out the trans fluid for a different type (transfer case as well) New filters and I drove home from san diego with temp running 160. went up 1/2 mile of steep streets and it got to 175 max. Looks like the typ of fluid was the problem. I will post the name of it when I can get in touch w/ the mech. who did the work.

 

[TrentNell]

My trans temp is always 100 degrees hotter than the outside temp running a race tune and driving normal. I think 200 is too hot! Just my 2 cents

once the allison is built up and pressures are raised 180-200 becomes the norm even with a better cooler . when my truck was stock it never went above 160 .

 

[DZLHUMMR]

Update: It is STILL getting to 225 on steep hills at low speeds???? It Does have TWO trans. coolers. I'm baffeled? Slipping W/ 10K miles on it? what else could be causing the heat? Fluids are right on now????

 

[mytmousemalibu]

Like i mentioned before, is the oil cooling system flowing properly? You can have the whole truck stacked with coolers but if there is a restriction in the system somewhere, your not cooling much. Could be a simple as a (rubber/steel)pinched line. I've heard of defective hoses that look fine outside but has a "flap" of rubber inside clogging the line.

 

[DZLHUMMR]

well Predator checked all the lines and coolers and said they felt the coolers and they got warm as the transmission got warm indicating that there WAS flow through the two coolers.

 

[DZLHUMMR]

Predator DID check all the lines and felt the coolers getting warm as the trans got warm and they belive there is no obstruction to the flow.

 

[DZLHUMMR]

sorry for the DBL post

 

[racinmike77]

simply putting too much fluid in can cause high temps.

 

[Mike L.]

If your Alli is not overfilled then I would check the size of the cooler tubes. I don't know what kinf of fan or coolers you are running. Be happy to look at it for you.