Transmission Cooler Recommendation for a 2006 Nissan Titan Towing Trailer Through Mountains

Question:

The original transmission just went in our Titan. It had 193K on it. I think it was because we started towing a 26foot travel trailer. We are replacing it with a used transmission that has 85K on it. I want to make sure this replacement transmission will not blow as well so were thinking of adding a D13503 transmission cooler. Will that be big enough? The GVWR of truck is 9200 lbs. The GTW is 4350 dry. Not sure of the GTW loaded as we havent been to the scales yet. Probably going to be around 6200 lbs? Trailer tongue weight is 500 lbs. We use weight distributing equalizer bars as well. We travel on some hilly and mountainous terrains. If these figures are accurate, will the D13503 transmission cooler be all we need for towing? Do we also need to increase the size of our transmission oil pan? Looking forward to your reply.

asked by: COLLEEN E

Expert Reply:

193k miles out of a transmission that was used to tow a trailer is a pretty reasonable amount actually. Especially if you were towing in the mountains.

That being said I would recommend going with the biggest cooler you can fit in front of your radiator as you really can't over-cool a transmission. The part # D13503 is a great solution that works for most people and measures 11" Wide x 8-3/4" tall x 7/8" deep but if you can fit the bigger part # D13504 which is 11" Wide x 12" tall x 7/8" deep you would be much better off.

Going with a larger transmission pan would help as the more fluid you have the easier it is to keep it cool but realistically you wouldn't gain much by that. The # D13504 would work well for you. I attached an install video that shows a similar install.

expert reply by: Jameson C