Towing Trouble?

daviddsims · April 8, 2008

Guys I have an 02 Sonoma with the 4.3 motor in it. Recently I bought a 14 foot single axle trialer that weighs about 1100 pounds. I also had two 4 wheelers loaded up on it bringing the total weight to at most 3000 pounds. I drove mostly interstate for a 150 miles and some backroads when I noticed it starting to run hot. The whole way home it stayed up close to 3/4 on the temp gauge but never in the red. I just put a thermostat in it and when there is no trailer it runs perfect right below 210. I checked all the usual stuff but everything seems good. Surely this truck should be able to tow 3000 pounds without a problem according to the owners manual it says about 5000. It was about 75 degrees when I towed in the day and about 55 that night when it still ran hot. Anyone got any suggestions? Thanks.

98silvz71 · April 9, 2008

Guys I have an 02 Sonoma with the 4.3 motor in it. Recently I bought a 14 foot single axle trialer that weighs about 1100 pounds. I also had two 4 wheelers loaded up on it bringing the total weight to at most 3000 pounds. I drove mostly interstate for a 150 miles and some backroads when I noticed it starting to run hot. The whole way home it stayed up close to 3/4 on the temp gauge but never in the red. I just put a thermostat in it and when there is no trailer it runs perfect right below 210. I checked all the usual stuff but everything seems good. Surely this truck should be able to tow 3000 pounds without a problem according to the owners manual it says about 5000. It was about 75 degrees when I towed in the day and about 55 that night when it still ran hot. Anyone got any suggestions? Thanks.

Do you have a tranny cooler installed on it? My old 98 Silverado would run hot without an external tranny cooler installed. I bought a Hayden HD tranny cooler and the temps stayed closer to 210 while towing instead of above the 210 mark. Normally the engine ran at 180 by itself. Most of the time its the transmission heating up the radiator so then it heats up the engine.

daviddsims · April 9, 2008

No I dont have a tranny cooler installed. I didnt think I needed one for just about half of the recommended weight. I may look into adding one.

daviddsims · April 16, 2008

I am really at a loss now. I have been running just the truck by itself for the past couple weeks and it has ran perfect with the a/c on also. I hooked back up to my trailer today with just one 4 wheeler so I may have had 1500 pounds total and it started running hot. I have flushed the cooling system out also and just dont know what it can be unless the truck just isnt strong enough to tow anything. Anyone got any ideas? Thanks.

Mikeee · April 17, 2008

How many miles on your 02?

Have you had the trans checked by a "reputable" trans shop?

daviddsims · April 17, 2008

How many miles on your 02?

Have you had the trans checked by a "reputable" trans shop?

Have 140000 miles on it. It shifts just fine. Just curious why would you ask?

98silvz71 · April 17, 2008

Just invest in a cooler. It's only about 50-60 bucks and you can install it yourself. I got a Hayden HD trans cooler and the adaptor fittings for the radiator for about 56 bucks from Oreilly's. Thats what solved the heat issues in my 98. I had 146,000 miles on it too with a rebuilt trans at 97,000 and it could still get hot. Other wise check your water pump flow and maybe you could check that fan clutch. If it is bad the fan might not be pulling enough air when it gets hot for awhile. Check for leaks around the shaft to the water pump. Other than that I'm out of ideas cause I checked all those when I had my problems.

Mikeee · April 17, 2008

How many miles on your 02?

Have you had the trans checked by a "reputable" trans shop?

Have 140000 miles on it. It shifts just fine. Just curious why would you ask?

Well, this see....

The "reputable" trans shop could test drive for issues.

The "reputable" trans shop could hook up the 'puter and check various signals.

The "reputable" trans shop could drop the pan, which will allow them to check for "signs" in the bottom of the pan and kinda read them like "tea leaves" for developing issues.

Just because it drives fine for you does not mean that there is not any issues.

Just like you desktop 'puter.

Just because it "sounds" OK does not mean that there are not any issues.

A "reputable" geek could diagnose near death issues.

And as mentioned ... get stacked plate external cooler.

My 3¢

daviddsims · April 18, 2008

Well I called the radiator shop and they are gonna check the whole cooling system out for me. I do have a transmission cooler on it because there is a line coming from the transmission to the radiator and back out. Will see what they tell me tomorrow.

Mikeee · April 18, 2008

.... I do have a transmission cooler on it because there is a line coming from the transmission to the radiator and back out. Will see what they tell me tomorrow.

We are referring to an EXTERNAL cooler.

Just about the whole world has the internal cooler.

Let us know that the rad shop has to say.

daviddsims · April 18, 2008

Well just got back from the shop, they said that the radiator was pretty clogged up and they rodded it out. They think it had just enough flow under regular load to stay cool but when pulling anything the radiator was just too clogged for good flow. Hope that fixes it. I also had it lined up and they said I need a new steering box thats why there is slack in the steering wheel.

Godti · April 18, 2008

Im not telling you how to spend money, but I agree with everyone about investing in a tranny cooler if you are going to tow anything. $60.00 for a cooler and hardware vs $2500.00 for a new tranny.

daviddsims · April 19, 2008

Yeah I am gonna check into the tranny cooler. I will start looking around and seeing about getting one. Thanks everyone for the suggestions!

C & A s Dad · April 19, 2008

Shane, if you do the external cooler I would strongly recommend a stacked plate cooler and Hayden makes them in about 4 sizes. If you live in a warm climate, get the 11 x 11 x 3/4 if you live in a climate where the temps are very low in the winter you need to stick with one about 7 x 11 x 3/4. It is rare but you can overcool the fluid if the outside temps are really low.

Also, I would suggest you run it in series just as the MFG's do. This means the fluid will still go from the trans to the internal cooler in the radiator then to the ext cooler and then back to the trans. This is the OE method and the best IMO.