Transmission Cooler Needed? - I have a 2010 Chevrolet Silverado LS with a 4.8 Engine with 37000 miles . Recently pulling my bass tracker I noticed coming up the boat ...

I have a 2010 Chevrolet Silverado LS with a 4.8 Engine with 37000 miles . Recently pulling my bass tracker I noticed coming up the boat landing the transmission temp and engine temps both shot up. The engine temp roughly hit 212 and the engine got close to 225. I heard the fans kick on and the temps quickly dropped. When i got out of the truck you could smell the truck had heated up. It has done this twice. Two different chevy dealers couldnt locate the problem. One told me to add a external transmission cooler. Is this a good idea? Anything I need to have them look for? I'm not to mechanically inclined so I'm depending on yall.

That temp does not sound too bad. It sounds like the fans are doing their job. How heavy is the boat you are pulling? Does it weigh more than the rating of your truck? If not I'd say you should be fine.

Do you use Tow/Haul Mode? If not you should as it will adjust the transmission shift pattern to reduce shift cycling, providing increased performance, vehicle control, and transmission cooling when towing or hauling heavy loads.

I agree, those temps don't sound too bad at all. And an auxillary trans cooler is never a bad idea if you tow frequently. I'm not sure what you were smelling though... Maybe a little coolant or trans fluid leak that you just happened to smell because the fans were on and blowing the scent around..

I agree with above, I tow my trailers ( 6x10-6x12 utility ) and use towhaul with no problems.

From what I read of the original question it is not during towing but pulling the boat up he boat ramp. Could be wrong. If the problem is pulling up the ramp try 4wd low if the truck is 4wd.