I have a 2015 RX350 AWD with factory installed trailer towing package. I would like to pull a boat on a trailer, total weight 3400-3500 pounds for a distance of about 3000 miles. Some of the route will be hilly but no long or steep climbs. The factory build sheet says the trailer towing capacity is 3500 pounds. Does anyone have experience pulling trailers over long distances? What drive train problems, if any, did you experience? What effect, if any, will this have on tranny life? Last car was 2008 RX350 AWD and the lock-up torque converter gave problems resulting in replacing the trans at about 150K miles. All things considered I would prefer to avoid duplicating that experience. I have looked but found no threads dealing with this.

 

I towed an enclosed 6x12 camper about 1100 miles round trip with no mechanical problems last summer. I had recently changed the trans and diff fluid, and plan to change them again this summer. I plan on towing it on multiple 600 mile trips this summer. Your boat will be heavier but a lot less of an air brake than my trailer.

My RX was happiest at 55 in 5th gear, but it was not a problem to tow at 70 when needed. Fuel consumption goes up drastically with speed with a big trailer. I averaged 12mpg on my 1100 mile trip. I have Air Lift helper springs on the back

My RX had about 150k miles on it at the time.
Keep in mind that a highlander with the same engine and trans is rated for 5000 lb.

 

I wouldn't pull something that close to the load rating over mountains or long ranges, but... It'll probably be ok.
My fuel economy literally got cut in half by towing a simple motorcycle trailer (enclosed) on a highway. It's ludicrous.

 

My wife's 2015 RX350 FWD (now at 75,300 miles with three successive Toyota WS ATF drain-and-fills done last summer at 65,000 miles) has the factory towing package but I would never tow anything with this vehicle. These Aisin transmissions are mediocre at best. I have a 1999 Dodge Ram 5.9 V8 and if I need to tow anything, that truck automatically gets the job.

 

Timely thread! Does anyone know the tow capacity of this generation or RX? We have a 2013 and from a little internet digging, it's between 1500 and 3500 lbs. Our RX does not have the factory transmission cooler.

 

MY advice id to get something that will tell you the transmission fluid temperature live. As long as you don't overheat the transmission you'll be fine.

They sell phone apps with Bluetooth dongles, or get a dedicated gauge.

But if it was me, I'd rent a truck.

 

Thanks to all who replied. Upon further digging I found mention in the warranty/maintenance booklet about transmission service but it is unclear what the recommended service interval is. Nevertheless, if I end up towing the boat trailer more than just a few miles locally, I'll have the transmission serviced at a dealership. Unless towing a trailer or in off road conditions, it appears no transmission service is required.

 

I do not see that you specified the mileage on your RX. I recommend you follow the severe service interval for transmission maintenance if you hope for it to last over 100,000 miles and to tow anything at all. This means changing the fluid between 50,000 and 60,000 miles. The goal is to change the fluid before it begins to deteriorate so as to preserve your transmission and minimize wear of the clutch plates and solenoids. There are more than a few threads discussing this issue if you do some searching.

The goal is preventive maintenance. Note that some dealers will not do this transmission fluid exchange or change and will say it is sealed forever etc etc and they are full of crap. Just call around to all local Lexus or Toyota dealers to see who will do a transmission fluid change. This exact transmission is used in Toyotas also and we took my Niece's ES350 (same transmission) to have the fluid changed at the local Toyota dealer who also did a coolant and brake fluid change for a package price. So ask about such deals when shopping.

Lexus only wants your transmission to last long enough to get through the warranty period and to state that maintenance costs are low by skipping more expensive items such as the transmission fluid service and also the transfer case and rear differential fluid changes.

 

Personally I would not do it. I've towed trailers with a Cummins diesel trucks up to 17,000 lbs. Towing a boat with that weight with an RX for 20 miles should be no problem, but 3000 miles is another story. It's not just the boat and trailer. It's also the gear and fuel at 6 lbs/gallon, which adds up fast. It is not just the transmission you will have issues with, but also the braking downhills etc. Also realize that the RX has a short wheelbase. Short wheelbase vehicles and increase weight of trailer is a recipe for disaster on the highway causing it to not be stable and possible fish tale and not to mention crosswinds. Rent a truck or have the boat transported.

 

What trailer hitches have y'all had installed on your RX vehicles? My wife has MS and she is probably going to need a powered chair to get around more. She can walk for a little while now, but not far. I will have to build a pivoting platform for her to roll the chair onto. I am in the investigation phase atm. dont want to get a cheap trailer hitch that will fail when she has her chair.

 

I installed the Curt 13143 hitch. So far it's been great for my smaller trailer. Took about an hour to install. There was a small cut in the rear plastic cover that had to be made. Easily done with basic tools, though.

 

Look at https://www.etrailer.com/?gclid=Cj0K...YaAuh0EALw_wcB

I too have a Curt hitch, as do a majority of members. etrailer has a good selection of hitches and great installation instructions including videos.

 

I have never towed that far with the 350, but I do tow A LOT locally. Just yesterday I had a 45 mile run to go get some railroad ties. (2500 pound load). If you are worried about a long haul like that, grab you a universal transmission cooler add-on and go with that. It's what I did to my little 2000 Rav4. I took that thing cross country with a 2k pound load. It only has 120'ish horses. Made the trip just fine, except for the severe lack of power on mountains, and I still drive it to this day with 303k miles. Anyways... back to the subject at hand. Use manual shifting up hills. Keep it in 4th gear. Use 5th gear for everything else. You should be fine.

edit: I concur with the post saying to flush your transmission. It's easy and you can run 8 or 12 quarts though it in fifteen minutes.... once you have the transmission up to temp. Helpful info.... drive your car to raise the transmission temp. Otherwise you will be like me, Sitting for half an hour while your car is idling... twiddling your thumps. Waiting and waiting for the temps to rise.

edit again: the brakes are what you really need to be worried about. They aren't that good. And you don't want to be using your transmission to downshift and slow down. Just be sure to have a good set of pads on there that can handle the heat.