We have a '07 tahoe in the garage!!! Nice ride, but not the greatest tow vehicle. I don't know what you boat weights in at, but I don't like towing more than 5k behind our (rated for 8500lbs), but we are in the rocky mountains! I have tried to tow our boat with ours just for testing it out. thumbs down, but we weight in at 9k ish.
As far as a trany cooler, you got one. You also have a trany temp gage built into the dash info center, keep a eye on the trans oil temp while towing, if it climbs to 210-220 slow down and let it cool and try to keep it under 200, preferably 185-190 deg F. In fact watch all the temps.
If temps do climb, make sure wifey sees/knows this, show her the little tahoe is a great family car, but by no means a great tow vehicle and your just tearing it up!!!!
The '07 tahoe will handle you boat fine, you just will have to take it easy.
Good luck on showing wife you NEED a truck.
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2000 248 5.7L DP
'92, '94 SXI 750, '08 STX 15F, '12 Ultra LX 300
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