mikey00

It's called "Towing Preparation Pkg w/Transmission Oil Cooler". It's listed under performance features on the left side of the sticker. It was standard equipment in 2001. I don't think it was there in '99 but was introduced in '00 or '01. This includes the plug which is very easy to get at in a black plastic box under the rear of the RX. The controller must also be added and is another easy plug in. The kit you used is for a car without these plugs, so you must manually tap off taillights, etc. A lot more work, as you indicated. If I get a chance I will scan a 2001 RX window sticker and post it.

AgSport

My SilverSport didn't have that feature, i.e. no such listing on my sticker. Mine wasn't pre-prepped for the tow package; no trans oil cooler or larger radiator on this RX. I didn't order it since my needs were for very infrequent use. It's only towed two small trailers in 20K miles but nice to have just in case. But I use the hitch frequently for a hitch-mounted bike rack (no lights required there).

The kit was generally easy to install but lots of component parts to provide a clean, near factory-direct appearance and certainly reliable performance; so having the detailed instructions made it much easier. Taking off the interior panels made me a little nerveous since at the time the RX only had about 200 miles on it and I didn't want to ding up the plastic; it all came out fine. My Lexus friend looked at it after I installed the electronics and he said it looked exactly like how their shop would have done it (it should have since I followed the factory instructions/diagrams). NO splicing of wires, just Plug & Play...everything I needed was in the kit.

Bottomline: there is/was a towing package wiring harness kit available for (at least my model) RX and the install was perfect as far as I'm concerned. I think anyone thinking about adding/needing the trailer wire harness should get the factory stuff so you know it'll fit and work properly.

mikey00

I would be very suprised if the connector is not on your RX for it was standard equipment in 2001. Mine is also a 2001 SS, but I guess anything is possible. There have been many discussions in the past over on the Edmunds board about what is needed for the trailer wiring install. I guess what I am saying that before someone goes through the pain of installation that you did, they should first check fot this plug. The pigtail and module are also factory items and much easier and neater to install. I think the guys who started this post are just about there. Hopefully when they complete the install they can confirm what is needed.

LexRX

Here is the window sticker from my 2000 FWD RX. My question is, if I have the transmission oil cooler why don't I have the oil-temp light that I see light up on startup on AWD RX's?

mikey00

I guess I don't have to scan my sticker now. The towing prep line on mine is the same as yours and mine is a AWD/2001. Are you sure you need an oil temp light to have an oil cooler? I'll check mine tonight. We are probably getting a little off topic from the original wiring question, but what the heck, your the moderator.

LexRX

I had the dealer install my hitch before I bought my RX, it didn't have one from the factory. This was in 2000, so it is a different hitch from the 2001+ RX's. It is my understanding that Lexus began doing something different (other than the physical hitch design) on the 2001+ MY RX's.

It's hard to say exactly what the towing preperation package actually includes other than the transmission oil cooler. Before I took delivery of my RX I told the salesman that I had to have a triler hitch installed first. He quoted me $400 to have it done; we split the difference at $200. Again, I had this done before I received the RX so I don't know what was already there and what wasn't. But $400 was the price to install the hitch and wire the vehicle. CoachMan, I have the converter sitting in my spare tire well if you want a picture of what mine looks like.

AgSport

Here's something new...
Got this from Kelley Blue Book.com

Lexus Accessory Package, model TO-Towing Package • 2WD cost: $128.00, retail: $160.00
(Std. 4WD Model) (Req's Hitch-model DH) Includes Larger Radiator & Transmission Cooler.

I read that as to say the "Towing Prep-package" is standard on the 4WD model and is optional on the 2WD model. Further, that also means all the 4WD models already have a larger radiator + a trans. cooler. That makes sense since the engine needs to work harder all the time (i.e. more load on engine & trans, etc). + if you go off-road (to use the 4WD), again generally, there is even more load on the engine, and requires additional cooling.

mikey00

All this is true, but I bet they do not have 2 seperate wiring harnesses one with the plug and one without. You can probaly do the easy plug in install on all of them. But LexRx above has towing prep standard on FWD.

gp1200x

OKay...now this brings up another question I have. I am pretty sure my 99RX had no plug on the cabling for a trailer attachment. I ripped everything apart and saw no such plug on any cable underneath the vehicle. Wiring up the vehicle was the same setup I have done on my other vehicles so it wasn't a big deal.
My question is about the tranny cooler. I recently ordered another radiator....haven't installed it yet since my original leak appears to be plugged for now at least....

Anyway my 99 AWD has a tranny cooler in the bottom of the radiator and it is from the factory. When I orderd the new radiator there were too to choose from...I ordered the larger one since it actually was priced lower. It has a tranny cooler in the bottom too. Are you guys saying that if the trailer prep package wasn't installed, the radiator would not have a built in tranny cooler in the bottom. Or are you guys referring to another optional tranny cooler that comes with the trailer prep package? Do some AWD RXs not have the built in tranny cooler in the bottom of the radiator? I thought this was standard on AWD RX models?

mikey00

I don't think the trailer harness plug was added as standard equipment until 2000 or 2001. The plug is located in the black plastic housing under the spare. You have to access it from under the RX. If you wanted to add trailer wiring on a 1999 you had to use the kit mentioned above which took 4 hours to install. All I know about the tranny cooler is it is listed as standard equipment on my 2001 AWD and also on LexRX's 2000 FWD as indicated on his above sticker. I never took a look at it.

SAhearn24

I own a 2002 Lexus RX300 and purchased a tow lighting cable after market. It fit the connector under the back of the RX300 perfectly. I even said to my wife that nothing is ever this easy. Then I rented my first trailer a couple of weeks later and came to the realization that there was more to it than a simple cable. So I read through this thread, but could not come to a conclusion on what part was needed. It sounds like a cable that is connected in the rear storage area (part 08921-00031). Is this correct for the 2002 RX300?

Thanks in advance!

mikey00

The part # you listed is for an RX without the towing prep package (pre-2001). It would work but would be a lot of unnessary wiring and more possible failure points. You already have the towing prep package if you were able to plug in the cable. You just need to add the controller.
From page 1 of this post:
"UPDATE: I just verified with the parts department that the PowerConverter PN # 08921-48070 is right, Lexus of Kendal is out of stock, and they want $106.74."

ravengotu

I just purchased a harness from a lexus online store see pic

I was wondering if this looked like the one from Lexus as they said it was....I have a 2000 with Tranny cooler installed, . Lex of sacramrnto wanted 200.00 for the harness

bob2200

I have a 2002 FWD RX300 and that's my recollection too. I paid the extra $160 for the towing package on a special order. They delivered it with the hitch too, and didn't charge me extra for the hitch, since I hadn't ordered it.

mikey00

That looks like it. Where did you get it and how much?