Transmssion Temp

Joe28443 · September 30, 2008

We just got back from a short trip to the beach towing a 5800# dry TT with my 03 Chev 1500. I have a scan gauge ii and the tranny temp showed 194-199. I kept it between 55-62 and it was a flat surface the entire trip. Does this sound about right? I am thinking of getting a high capacity transmission pan to be on the safe side. I have a transmission cooler but you can never have to much. What point does it start to overheat? Does anyone have a high capacity tranny pan and are you happy with it and what are your temps?? thanks

Bish · September 30, 2008

We just got back from a short trip to the beach towing a 5800# dry TT with my 03 Chev 1500. I have a scan gauge ii and the tranny temp showed 194-199. I kept it between 55-62 and it was a flat surface the entire trip. Does this sound about right? I am thinking of getting a high capacity transmission pan to be on the safe side. I have a transmission cooler but you can never have to much. What point does it start to overheat? Does anyone have a high capacity tranny pan and are you happy with it and what are your temps?? thanks

I've always heard to keep it under 200 or 210. I saw a chart of trans fluid longevity and IIRC it started to decrease at about 210 with DRAMATIC decreases in fluid life above that.

HERE is one chart.

I think you are fine towing what you tow. Watch the torque converter unlocking as that will quickly heat up the fluid. A bigger cooler is never a bad idea unless it is so big it never gets up to temp.

Joe28443 · September 30, 2008

I am trying to keep from buying a HD at this time, I thought maybe a deeper pan with an extra 3Qt capacity would drop it down enough to give me peace of mind a little longer. I am wanting to take my TT to the mountains but I am a little scared at this time because lack of power and the trans temp. But I also just got back from a trip and I see these people towing campers alot longer than mine. One guy I taked to had a pull rite hitch and towed a 28ft 6700# with a lincoln navigator. It maybe that my truck can handle more than I think it can.

C & A s Dad · September 30, 2008

Joe, you are towing a similar weight camper to mine. I am towing a 29 ft Sunnybrook that weighs 6500 loaded and am doing so with a Yuk XL 5.3 with 4.10 gears.

I would ask a couple of questions.

You say you were running 55 to 62. Were you in 3rd?

I would assume you were using the T/H feature?

Is your Trans cooler the factory unit?

Where do you live? I would like to know what your avg winter temperatue is?

I would say your temps are not too high at this time but if you were in 95 degree heat and pulling some hills, you will see your temps really climb. GM has the warning light to come on at 250. IMO, this is far too hot, at least for me.

I upgraded my OE cooler to a Stacked Plate cooler that is 11" x 11" by 3/4" and moved to a full syn fluid by Amsoil. This cooler is exaclty like the OE cooler except it has about twice the surface area. I tow in 3rd with T/H engaged in relatively flat country with modest rolling hills. My temps run around 160 on a 95 degree day. My highest temp has been 172.

I would suggest a larger cooler before you look into the pan. I say this for a couple of reasons but primarily, I think you will have a clearance issue with many of the high capacity pans avail. There is very little clearance on mine between the rear of the pan and the crossover pipe. I researched this pretty good and found one from PML Covers CLick here that would fit my truck but elected to go with the larger cooler. I did add a finned high capacity diff cover from them.

I will be happy to send you some pics of my cooler upgrade if you decide to go this route. I would need you to send me your e mail address in a Private Message if you decide you want to take a look at the pics.

I will be happy to help you if I can.

Joe28443 · September 30, 2008

Yes I am running in 3rd with the tow haul engaged, I have an aftermarket tranny cooler. I live at the beach here in eastern NC and it does not get too cold here. I am concerened becasue I do not want to destroy my tranny and I do not want to keep traveling on flat country as I like going to the mountains of NC and I also do not want to be bothered with overheating if I decide to go on a 10hr trip. I like to keep it tached at 2400-2500 RPM and at 60 mph. I will send you my email. thanks

C & A s Dad · September 30, 2008

Take a look at the pics I sent.

Do you know if your cooler is a tube and fin style or a stacked plate cooler. The tube and fin coolers do the job but are not nearly as efficient as a SP cooler. It takes a much larger tube and fin cooler to offer the same cooling as a smaller SP cooler.

Shoot, if you already have an aftermarket cooler, it would be a simple job to upgrade it if necessary.

From your RPMs at 60 it sounds like you have 4.10 gears. I run in the 2400 to 2500 range as well. I have found my 5.3 really likes running between 2200 and 2600 or so. This is what I call "the sweet spot".