Tranny temp problem

[bigbobed]

Ok, I changed the filter on my Allison. Now I go to the book to look at the procedure for checking the fluid level. "Bring the trans to normal operating temp, 160-200 degrees." How the heck do I do that? Runing empty it never gets to 150. Towing my fiver it usually runs slightly more than 150. Only goes hotter if I'm in hills or a big head wind. Once in a great while gets to 200. Looking at the dip stick there is quite a spread from cold to hot, so I assume it expands quite a bit. Hate to overfill. Right now it's at the bottom of the hot zone at my "normal operating temp." I added one pint of fluid including filling the filter.

[sonofagun]

bigbobed,

Just drive the truck around for 10 or 15 minutes or until the trans guage gets to its normal operating range. Then check the fluid level. GM guages are approximate issue units at the best of times and few read the same.

Bob

[Billy14]

bigbobed,

Lucky you. My tranny temp gets up to 230 deg. runnin empty. Two days ago it slowly crept up to 210-215 according to the gauge. I was close to my dealer, whipped in the service dept., & the service manager hooked up the tech 2. No codes set. 213 deg.
The gauge on my truck is accurate. They agreed. this is too hot but no one has a clue as to why. Called GM engineering but have not heard back to date. A/C on drives the temp up much quicker. Condenser is located in front of the tranny cooler. Guess they want us to be cooler than the tranny. I agree, but I still think I have a problem.

Billy

[mark45678]

billy 14 My mind is questening ac in front of trans/ps cooler? I have never seen this combo,the trans is allways out front just behind the bowtie or gmc symbol! I reall dont like the Idea of putting the cooler just behind the bowtie grill , most of it will not see full air flow! the GMC one is ok! 2nd it must have a thermostat some place to keep things in check for winter. like most will tell you they run at 150~160 unloaded year round!

[DmaxMaverick]

Mine runs 130 to 140 unloaded, and 1 to 2 lines below 200 with my 12K 5'er. This is in the summer with the A/C on uphill. I've tried to heat it up, but it just won't. My dealer also confirmed that my gages (except the fuel :mad: ) are dead on. My tranny has been flushed and filled with Amsoil. Before the Amsoil, the temps were about 2 lines higher across the board.

All things being equal, it appears you have a problem with those temps. Let the dealer handle it. Who knows? They may just get it right.

[Lone Eagle]

Billy14, My 02 2500HD DMAX has an auxillary trans cooler right behind the grill Bowtie emblem. It is first in line for cool air. You might want to see if you have one. Later! Lone Eagle ;) PS: This cooler is a itty bitty thing. Two big Dragon flys would plug it up. Maybe that is why it is behind the grill. :D :D

[ 05-31-2002: Message edited by: Lone Eagle ]</p>

[IndigoDually]

I don't remember how hot I have seen it but some weight behind Your truck up and down hills, add some heavy duty grade braking and the temps will rise.

John

[Billy14]

Hey guys,

Thanks for all the input. I personally haven't traced the lines but have relied only on my dealer at this point. Yes, if the little cooler behind the bowtie is in fact the tranny cooler, it's there & in the right place. Guess my dealer needs to be back in school. Not plugged up, no big butterflies, clean as a whistle. When I got into this before, someone posted that tranny temps over 200 would shorten the life by 30 - 40% (I think this is correct). Doesn't sound good to me!

I'm serious though, I have made posts before regarding what I feel is way too hot temps for this rig with no load & ambient air between 85 & 92 deg. The engine never gets over 195 with or without load. Something has to be wrong. My opinion.

Billy