We have narrowed down are suv search to these 2 models (2007).
We are planning on buying a 19 foot boat, and wondering which model is better for towing? The boat weighs around 3800lb with trailer

I have researched tow hitches and it seems it easy to add on.Should we try to find one with the trailer package already on? Does a factory trailer package have a transmission cooler built it?

 

Check with your Lexus dealer, but I believe the RX series has a maximum tow weight of 3500 pounds.

 

Good question. Does your trailer have brakes? Usually it's not pulling which is the issue, it's stopping.

Ditto on checking with the dealer..

 

Thanks for the replys.
The trailer has disc brakes, and I will be towing about an hour on a mostly flat road, but in 110 degree heat

 

Make sure the RX you choose has the tow prep package which includes the trans cooler.

 

Thanks. How do I check to see if it has the trans cooler?

 

Brian06, I never used mine to tow but I believe the trans cooler in front of the front passenger tire. I would think the dealer could tell you if the RX has it.

 

I think towing a big boat with an RX would be a very bad idea. You will probably be killing the transmission, if not racking the body. Unless you have a featherweight boat, go for a full size suv with a frame.

 

It appears that you are exceeding the safety limits of the RX hitch. This hitch as a maximum tongue weight of 350 and gross trailer weight is 3500 pounds. Your boat weight is 3800, by the time you add gear and fuel you are easily exceeding 4000 pounds. If the boat has a high tongue weight you will squat the vehicle and require a weight distribution set up. I suggest you think twice and research this carefully.

 

What kind of 19 footer with the trailer you have in mind? If you still didn't get a boat look at "Key West" manufacture with aluminum trailer. I ran the calculations "19 footer with center console" 2500lb and the aluminum trailer 500-600lb for my self (I'm planning to get the fishing boat soon and already have RX400h in house). And don't put fishing rods in the boat
We should be able still make the safe limit. The question is can we pull it out of the water...

 

I towed around 2000 lb once for 700 miles (RX350). The transmission would hunt around for 4th 5th going uphill. I suspect the tranny would blow out if I did it more than a couple times a year. And I DO have the towing package dealer installed.

I suspect the extra battery weight of the RX400 would really push you over the limit.

 

buy a dodge if ur gonna tow, lexus is for chillin and pimpin in

 

This is why towing is ALWAYS supposed to be done with overdrive OFF. With OD on, the torque converter will frequently unlock, which causes the temperature in the transmission to increase and will eventually cause transmission failure. Towing in 4th allows the TC to stay locked for significantly longer stretches, lengthening the life of your tranny.

The 1mpg you save by towing in 5th gear isn't worth the $4,000 bill you'll get down the road...

 

+1
When did landscaping even with a HD Chevy 2500 I drop it down a gear going up hill to prevent gear cycling.

 

If I told my wife that her RX was for chillin and pimpin, She would probability sell the car.