Hopefully someone could lend a hand with this. So this past weekend I go out to Yuma to ride some jet skis. I was coming from San Diego down the 8 frwy up the hills at night time and I am pulling two jet skis and have a little 90 quad in the bed...so as I was going up the hill I get on it about three times to do some passing. At the top of the hill right after the boarder check point I start to pick some speed back up and notice when I was in 3rd gear it made a weird noise (lound taping noise I would say) for about 2 minutes then shifted into 4th. A couple minutes later I was back in 3rd gear and came on a slight incline and it made the same noise but at the same time it spudered and shifted into 4th and went away. I took it out of tow/haul mode and let it be, I had no more problems after driving about another 2 hours?
Now when I came back on that sunday going back to San Diego the grade on that hill I belive is alot steeper, the truck ran fine all the way from Yuma but when I go to the buttom of the hill you can tell the truck was reving kinda high, so I was following my buddy and he was pulling his toy hauler so he was going kinda slow but at that time I notice my tranny level going up pretty fast(scared the hell out of me) so I went passed and made it to the top of the first hill I had to pull over and so did my buddy. At that time my tranny was at 260 and I know if I kept going it would have gone up. So I took the side roads with not that much grade
and the temp went down to about 210 to 220. I had too get back on the 8 fwy and a couple more grades to go but tranny temp never went back up. One thing I did notice notice is that when I finally made it back home
I got on it alittle to see if the tranny temp would come back up and from about 190 it came up too about 220 just like that? The mods to my truck are a 6in lift on 35's, silverline cat back exhaust, edge with ***. (was set on 2 tow mode) oh yeah the temp outside was about 110 or so. :help:

260 yikes!! I towed my 5000 lb. boat to Havasu and it was 117 outside.my tranny never got over 220 and that was only on small hills. sorry I cant help, just sharing how my truck did in extreme heat. good luck!! Mike L. or someone will help you

I was wondering azmxer I noticed you have the same lift as me and im running the 35" Toyo m/t. I came back from the dealer today and they said no codes came up. I see you have a power program as well on level three... I never put my juice passed 3? I tow on 2. The dealer asked me if when they had lifted my truck did they calibrate the tires to the tranny. I guess they go through tranny control module. Just wondering if you had this done to yours. I've been up other step hills with more load lifted with not a problem. They never calibrated it so I guess I need to do that, but after that happens will I still get the same problem?

Hopefully someone could lend a hand with this. So this past weekend I go out to Yuma to ride some jet skis. I was coming from San Diego down the 8 frwy up the hills at night time and I am pulling two jet skis and have a little 90 quad in the bed...so as I was going up the hill I get on it about three times to do some passing. At the top of the hill right after the boarder check point I start to pick some speed back up and notice when I was in 3rd gear it made a weird noise (lound taping noise I would say) for about 2 minutes then shifted into 4th. A couple minutes later I was back in 3rd gear and came on a slight incline and it made the same noise but at the same time it spudered and shifted into 4th and went away. I took it out of tow/haul mode and let it be, I had no more problems after driving about another 2 hours?
Now when I came back on that sunday going back to San Diego the grade on that hill I belive is alot steeper, the truck ran fine all the way from Yuma but when I go to the buttom of the hill you can tell the truck was reving kinda high, so I was following my buddy and he was pulling his toy hauler so he was going kinda slow but at that time I notice my tranny level going up pretty fast(scared the hell out of me) so I went passed and made it to the top of the first hill I had to pull over and so did my buddy. At that time my tranny was at 260 and I know if I kept going it would have gone up. So I took the side roads with not that much grade
and the temp went down to about 210 to 220. I had too get back on the 8 fwy and a couple more grades to go but tranny temp never went back up. One thing I did notice notice is that when I finally made it back home
I got on it alittle to see if the tranny temp would come back up and from about 190 it came up too about 220 just like that? The mods to my truck are a 6in lift on 35's, silverline cat back exhaust, edge with ***. (was set on 2 tow mode) oh yeah the temp outside was about 110 or so. :help:

I have no mods on my truck except for 265's for tires. I have kept an eye on the tranny temp towing back and forth from Martinez Lake, AZ to San Diego, towing or not towing, the tranny temp reads the same assuming outside temp is the same. It never has gone above 220. One thing I have done is changed the tranny fluid and put in Transynd. I tow a 21' Ultra, with a bed full of stuff and the boat I am probably around 5000lbs. I think the combo of the Edge and larger tires and probably not helping too much. You may want to consider a deeper tranny pan, Allison makes one as does Mag HyTec - those pans hold another 2 or 3 quarts of fluid. You may also consider an aftermarket tranny cooler.

I am working on extreme heat in our Allys right now. My cooler does a tremendous job but more can be done. I have some great ideas and will post something in the next couple of weeks. I do not believe a cooler larger than mine will make a noticable difference and a fan mounted on the front of the cooler helps a small amount. The problem lies elsewhere. I think this is going to be good for the problem overheaters out there. Most of the the guys running my cooler are not having a problem anymore, but there are some real hot Allys out there and this is for them.:ro)
mike

You better get mike's tranny cooler. mine never goes over 200 even in 110 degree temps.

Mike L., I have a question about an additional cooler. I'm soon to get a very large fifth wheel and towing it the mountains or hot FL could push the temps up. But, when not towing in the mountains in the winter, wouldn't that be hard on the Allison--not getting up to the operating temperature? Is there any flow restriction or additional backpressure? Thanks

In the Allison 1000 book that comes with the commercial trucks (and any Allison transmission for that matter) they state 100° minimum operating temperature. Depending on transmission types there are certain limited operating modes you can do below certain temperatures and it depends what type of oil you have in it (some of them can take 30w, etc) but the pickup transmission has most of this stuff built into software and it is a pretty safe bet you will be using ATF in it I would imagine;)

Birken

chevyhundo As far as I know there was no calibration done. I did change my tire size w/ the hypertech to correct speed , But just did that the other day not when I was towing to Havasu. Also when I tow my boat long distances i drop the hypertech to level 2, it just seems to act better.

My Ally runs warm just hauling my fat butt around with no load, in the twisty hills where I live, so I know it's gonna' need help when I really start to work it.

I just changed my Ally filter for the 1st time and have only towed a little with the new truck. Every time I get under the truck, I just keep seeing how close the return cooler line is to the exhaust. At speed there may not be much heat gain due to air cooling, but going slower the radiant heat must soak in.

Mike L: Have you done any analysis of this? I'm just thinking a simple insulator or even reflective sheild may help if the gain is significant there. Will be interested to hear what else you are working on. If GM doesn't step up and do a fix for my truck's cooling (EC as well as Ally), then I'll be contacting you on one of your coolers... :cool:

Towing my boat up an 8% grade 100 degrees outside doing 65mph my tranny got up to 270 and my engine got up to 260. Its in the service department right now getting checked, I'll let you know what they say. The hill was only about three miles long and then went flat and the temps went back down to normal, which for me is 210 on both tranny and engine.

[quote=jsthawk;633483]Towing my boat up an 8% grade 100 degrees outside doing 65mph my tranny got up to 270 and my engine got up to 260.

Wow! That's hot. I have an 04 LB7. I put Mike's tranny cooler on mine just to keep the temps down while having the camper on and towing the boat. It works awesome. We went to Havasu and then to Yosemite area. The rig in my sig weighed in at 16,900 lbs. I never got over 188 degrees tranny temp. Traveled in the daytime with the air on at 70-75mph. That was mid May and the outside temps were around 95. I figure it was a good investment as I intend on running this truck a long time.

Towing my boat up an 8% grade 100 degrees outside doing 65mph my tranny got up to 270 and my engine got up to 260. Its in the service department right now getting checked, I'll let you know what they say. The hill was only about three miles long and then went flat and the temps went back down to normal, which for me is 210 on both tranny and engine.

Were you in Tow/Haul mode?

DEWFPO

any word on the trans cooler for the 4500's yet Mike L? heck it heats up just sitting stopped with it in gear and the brake on. use it for making a living so things are getting somewhat desperate.

My tranny today just driving home from work in Boston and it stayed around 200. I was kind of nervous driving home, it has been pretty hot here this whole week. Another day under accelration it jumped up pretty quickly to 180-190 and went down. Today it stayed at 200 until I got home.

No, I was not in tow haul. I just got my truck back, of course they couldn't duplicate the problem. Took the boat back to the same hill with tow haul on (115 degrees outside), floored it all the way up the hill and the tranny and engine temp never went over 215. I hope that was the only problem (me not having the tow haul on), time will tell.:ro)

What's Mike's cooler and where do I get one? I'm getting ready to change tranny fluid in my dad's 04 3500 to synthetic and I mentioned to him that he should put on a better cooler. I just found out from him today that loaded his horse trailer weighs about 26,000 lbs. Only problem he's had(so far. I told him he was nuts for pulling that much) is tranny getting hot. By the way, does anyone have a good method for changing all the fluid instead of just what's in the pan.

Ever think of letting the horses pull the Dmax?

Ever think of letting the horses pull the Dmax?
He almost had to on his last trip down south. That's why I need an upgraded cooler. Are you the Mike that sells them? I am serious about wanting to buy one. Let me know which vendor you are and I'll order one from you if you're the guy.

My local dealer called me and said that I am the fouth person to have my truck looked at for the overheating issues, anyway they said they think they have a fix and ordered me a bigger radiator / volant cool induction system / and they think they might add a cowl induction hood. I took my truck back into the shop and and waiting to hear from them. I will update you when I get my truck back. All parts are being covered under warranty.

You don't need a bigger radiator. Seal the cooling stack. you wont believe the difference, that and cold air intake box will make ( a true CAI, not a KN, etc.).
The fan we have is more than enough, it is just stuffed into a poorly designed cooling stack.

You won't be able to overheat it again, if done correctly.

50 cents invested in foam and cardboard, brought my transmission down 20 degrees, including a lot of low speed improvement, all stock. Hardly ever hear the fan any more, above 30 mph either.