auxiliary transmission cooler 2006 LX 470 (1 Viewer)

[lxWolf]

Hi,

I've been hauling a camper trailer on and off over the past month (approximately 2,000 miles) with my 2006 Lexus LX470. Dry weight of the trailer is approximately 3,800# and I've got it hooked up with a sway bar and weight distribution hitch plus a brake controller. The engine temp warms up sometimes as I'm driving uphill at higher speeds but nothing in the red line just more than obviously if I was not hauling anything.

My question is- is there a way to install an auxiliary transmission cooler for a 2006 LX470 and if so, is there value in this addition to keep the transmission/engine at better regulated temp when hauling?

thanks!

 

[vcheng]

Hi,

I've been hauling a camper trailer on and off over the past month (approximately 2,000 miles) with my 2006 Lexus LX470. Dry weight of the trailer is approximately 3,800# and I've got it hooked up with a sway bar and weight distribution hitch plus a brake controller. The engine temp warms up sometimes as I'm driving uphill at higher speeds but nothing in the red line just more than obviously if I was not hauling anything.

My question is- is there a way to install an auxiliary transmission cooler for a 2006 LX470 and if so, is there value in this addition to keep the transmission/engine at better regulated temp when hauling?

thanks!

It should have one already, right up front.

 

[ramangain]

What are your actual tranny and engine temps?

 

[OEMGUY0720]

Thinking about doing this too maybe upgrade to a multiple row type of AT oil cooler (bigger and thicker) possibly using the same bolt/brackets in the front just not quite sure if someone already successfully did this.

 

[greasem0nkey86]

My question is- is there a way to install an auxiliary transmission cooler for a 2006 LX470 and if so, is there value in this addition to keep the transmission/engine at better regulated temp when hauling?

thanks!

One of the recommendations when towing heavy loads would be to install a transmission oil cooler to help keep oil temps cooler. As @vcheng stated, there already is one installed from factory. If you open up the hood, its behind the grill, but in front of the radiator.

There is a transmission temp light on the dash if transmission oil reaches a certain temperature, has that indicator light turned on when you have been towing?

 

[lxWolf]

Hi Greasem0nkey86,

No, never had the transmission temp indicator light turn on, towing or otherwise. I'm very new to towing and didn't realize there was a light indicator notification to begin with. I don't know what is the actual temperature, but going up hill hauling, the gauge can go from middle of the road up to two marks below the red line. If you can see the attached image - the needle sits at the yellow line typically not towing anything or towing downhill/flat and at it's peak (I've driven about 2K miles towing now) the line can get up to where the magenta arrow is shown on the image. At that point I'll slow down and it gets back to regulating itself pretty well. I've never driven it thru the mountains but have driven it thru some pretty consistent hills over several hours. Thoughts on the above protocols?

Since there is an aux cooler already factory installed (thank you for sharing as I didn't know this) is that sufficient or are there better after market options available?

thanks,

 

[gatormark91]

Are you driving with the OD on?

 

[lxWolf]

I hope I'm not driving with OD. For many years I had a 2000 Land Cruiser and it had an OD button on the shifter. The 2006 LX doesn't seem to have that. I'm assuming that "D" is OD? if that's not correct please share. I'm driving in 4th gear on the highways flat or hilly.

 

[abuck99]

With your towing usage/set up- Look into using a realtime monitoring device: scan guage, torque or blue driver so that you know exact temps and how and when to adjust your driving technique to manage ECT and TFT.

Adding (or changing) an aux cooler is unnecessary- the stock external cooler is extremely capable.

If you tow heavy and frequently, especially in hilly terrain you would be better served to put your money towards a different valve body in the transmission to eliminate slip/improve lock up: HD Nomad Valve Body

Wholesale Automatic Transmissions -

cruiserbrothers.com

 

[Ridgerunner78]

If you're worried about trans temp, then x2 on getting some kind of monitoring device. I run a Scangauge II with the PID programmed for trans temps. When I do tow it's pretty light, my camper is 1500# dry, and I've never seen the tranny warning light come on. Towing in the summer on the interstate (flat @ ~80 mph) I usually see coolant temps in the mid 190s, and tranny temps in the low 160s. The highest tranny temps I've seen on the gauge were just over 200 deg, which was odd as it was pretty much unloaded headed east from SLC into Wy on I80, and the outside temp was ~10 deg.

 

[baggar11]

On our '02, my experience has been that these transmissions and coolers do a pretty phenomenal job of cooling. Our family took our 3400lb(dry) trailer on an 1100 mile trip at the end of June. I snapped a pic after cresting a 20-25 minute mountain pass in 90F heat. Pulling 2nd gear at 45-50mph the whole time. As soon as I hit 3rd gear, temps dropped 10s of degrees within a minute. Highest tranny temps I've seen are actually when I back the trailer up on the side of the house.

Since we had packed for a 10 day trip, our trailer was over 4k easy. Lots of propane, wood, food, beverage, etc. Definitely recommend bluetooth or some kind of active monitoring. Otherwise, you're just throwing money at it without knowing.

 

[LCMoneyPit]

On our '02, my experience has been that these transmissions and coolers do a pretty phenomenal job of cooling. Our family took our 3400lb(dry) trailer on an 1100 mile trip at the end of June. I snapped a pic after cresting a 20-25 minute mountain pass in 90F heat. Pulling 2nd gear at 45-50mph the whole time. As soon as I hit 3rd gear, temps dropped 10s of degrees within a minute. Highest tranny temps I've seen are actually when I back the trailer up on the side of the house.

View attachment 2450076

Since we had packed for a 10 day trip, our trailer was over 4k easy. Lots of propane, wood, food, beverage, etc. Definitely recommend bluetooth or some kind of active monitoring. Otherwise, you're just throwing money at it without knowing.

View attachment 2450075

Do you run airbags to help the AHC, or does the AHC handle the tongue weight and load in the LX?

 

[baggar11]

Do you run airbags to help the AHC, or does the AHC handle the tongue weight and load in the LX?

I also have King springs installed, but other than that the AHC handles the load great.

 

[greasem0nkey86]

I hope I'm not driving with OD. For many years I had a 2000 Land Cruiser and it had an OD button on the shifter. The 2006 LX doesn't seem to have that. I'm assuming that "D" is OD? if that's not correct please share. I'm driving in 4th gear on the highways flat or hilly.

Your assumption is correct.
With the 5sp gearbox, "D" would have 5th gear is overdrive. When you're going uphill, best to drop it down to 4th gear, it'll help with less strain on the engine and transmission, towing speeds, and oil temps.

A few weeks ago I towed my friends tandem axle car trailer with 5 fullsize dirtbikes, a bunch of firewood, and camp gear, up and over the Sierras, from San Francisco CA to Reno NV. The weight definitely overloaded the AHC system and the rear stayed in low mode the whole time. It wasn't on the bumpstops, but it wasn't able to get the rear up to normal height. We tried rearranging everything on the return trip, same problem. Airbags or stiffer springs would have helped handle the weight better.

The transmission temp indicator light is under the water temp gauge. Labeled as #19 on the owners manual.

 

[OEMGUY0720]

@baggar11 what app/Bluetooth dongle are you using? Thanks!

 

[Mike NXP]

Shouldn't the concern be more with your engine cooling than trans temp since that is the gauge you are seeing increase close to the redline?

 

[baggar11]

@baggar11 what app/Bluetooth dongle are you using? Thanks!

Torque Pro on Android

 

[lxWolf]

Hi,

I bought an OBD2 bluetooth scanner and downloaded a iphone app called "Car Scanner". First off- this app seems really great and I recommend it.
Per my original post for this thread, I mentioned my engine temp, (not tranny, although I was concerned about the tranny temp initially) was warming up about 3/4 the way up the dial when I'm hauling on the highway often up hills at a higher speed.

I hooked up my car to this app and tested it- seems like the RPMs were exactly as what's on my dial so presume the other metrics are similar.

Not Hauling: on highway, on city streets, up hill or downhill, my engine temp ranged from 190-205 for miles consistently.
Hauling: on city streets/highways up to 55MPH, generally the engine temp was between 195-210
Hauling: on interstate 60mph-75mph generally 215-220 but would peak at 230ish when hauling uphill on interstate.

I've attached a graph to show the trip today hauling my approximately 4,000# trailer with the correlation of both speed and engine temp.

Is there something wrong with my engine cooling system? Is this an acceptable range for engine cooling temp when hauling something on the interstate? Any recommendations on next steps? Again i've got a 2006 LX470, weight distribution hitch and was driving in 4th gear for most of the time.

advice is appreciated.

 

[baggar11]

I'd be looking at my cooling system if those were my numbers. Generally, our LX stays around 185 most of the time. Whether it's a trip to the store or towing our trailer on the hwy. When it's real hot out and/or towing through a pass in 2nd gear I may see 200+ for a little bit.

 

[OEMGUY0720]

Curious when was the last time you change your atf and if was drain and fill type or if it was a comprehensive atf fluid exchange?