Should Transmission Cooler and Weight Distribution be Used With 2002 GMC Envoy?

Question:

I have purchased a 2005 Jayco J21 hybrid tandem axle travel trailer with a dry weight of #3875 and a tongue weight listed at #440. I also purchased a 2002 GMC Envoy SLT with a 4.2l, I6, DOHCit has the hitch installed with a 7way trailer connector. I also purchased a energizer brake controller, Should I get a weight distribution kit for it?Also should I install a transmission cooler on it? It appears that the radiator has a cooler in it which I assume is for the engine oil, while in front of the condenser there is another cooler about 24 inches long or so one line with fins, that I am assuming is for the transmission. Thanks for any help or info I can get from you.

asked by: Mike S

Expert Reply:

If you do not have a transmission cooler, I do recommend one while towing with your 2002 GMC Envoy in order to improve the vehicle's performance and keep your transmission from overheating and potentially failing. I suggest taking a look at the Derale Series 8000 # D13503, which is a confirmed fit for your '02 Envoy with a 4.2L I6 engine. You will need adapter fitting # D13035 to connect the radiator to the cooler.

I would also recommend a weight distribution system in order to make your towing experience both safer and less stressful. In order to choose the best weight distribution system, you will first need to know your total tongue weight (TW), which is the tongue weight of your fully loaded and ready to go trailer plus the weight of any cargo behind the rear axle of your 2002 Envoy.

To determine TW you can use a scale such as the Sherline # e99044 or by using one of the methods outlined in the help article on determining TW I've linked for you. The ideal system would be one in which your TW would fall somewhere in the middle of the weight distribution system's tongue weight capacity.

As an example, if your TW was 425 lbs, a great system would be the Equal-i-zer # EQ37060ET, which is for TW between 200 lbs and 600 lbs and uses friction within the sway control brackets to prevent sway. I've added a link to a review of this system for you, as well as links to video reviews of the other items I mentioned.