Towing Up A Steep Grade.....Extremes?

Howdy,

OK I have a 2013 Tacoma TRD Sport 4x4 with tow package. Towing a 22 foot Airstream trailer.

Total full loaded rig weight: ~9500 lbs.

So far I have towed it just fine back and forth from Tucson to Quartzsite and Yuma. One small grade heading into Yuma only challenge. Towed up that grade no problem going 65mph to stay with heavy traffic. ~4000 rpm.

Trans and engine temps rose (I have a ScanGauge II) but not quite to extremes. Engine got to ~205°F (lives at 193°F) and Trans ~185°F (lives at ~156°F. Seemed to stabilize and was not increasing as I crested. That's a short ~2mile 6% grade though... Mild ~65° ambient temps and a stiff headwind.

So, question. What are safe extremes to take it too on long grades?

I'm considering a San Diego run and have a few options grade wise.

Thanks!

 

Are you saying the trailer is 9500 lbs, or the combined weight of the truck and trailer is 9500 lbs. If the latter I'd think you'll be close, but OK unless you're using oversize tires. Assuming the truck is about 4500-5000 lbs and the trailer is 4500-5000 lbs you have enough towing capacity. You might be getting close to payload capacity if the truck is also loaded heavy. It might also be a good idea to actually weigh both the truck and trailer. You may be pulling a lot more, or less, than you think. I'd not worry about keeping up with traffic with that much weight behind a Tacoma.

 

Entire rig, Tacoma and Airstream ~9500 lbs.

I took it to Cat Scale and go that number and unloaded a bunch so maybe closer to 9000 now.

I was surprised! Airstream curb weight is 3300lbs + 4500lbs Tacoma = 7800lbs. I guess with full fresh water tank and my gear...... 1200lbs adds up fast!

Any ways... it ran just fine. 0-60 in safe enough time to get on typical fwy on ramp. The grades I hit were minor and no issue but have yet to pull a long sustained one and want to be able to know safe temperature tolerances before I get to them.

Knowing lawyers are more involved than engineers I'm sure the rating is lower and not at actual limits so feel confident in towing with it but one time too hot tranny will change all that in minutes!

Still cant determine safe operating temperature limits...

Any one else?

Thanks,

Az Tex

 

Ya know...

I'm not even sure which trans temp I have dialed in my Scanguage...... I know there's 2 or 3 sensors....

Hmm...

A

 

I have both dialed in. I have a 2005 V6 Double Cab with the 4.0L. I have an UltraGauge II which allows me to customize my screen. I monitor my Torque Cov., pan, Engine Temp and my alternator output (not for any resin other than I can't decide what I want in my 4th position)
From the research I've done, I've found mechanics posting temps North of about 220 deg F (for prolonged periods of time) is where you start to burn your ATF.

Since mine has the factory tow package, it comes with a factory Aux tranny cooler but it appears worthless to me because it's so small. However, because it's there, the two lines you need to add a decent-sized $45 aux cooler is pretty easy. I bought a 1.5" strip of aluminum (it will act as an additional heat sink) and bent out my own mounting bracket in place of the factory cooler. There's plenty of room to add a bigger cooler. The one I added is about is about 11"X11".

 

Howdy..

Well sad to say I gave up on the Tacoma as a tow vehicle for a 22' Airstream. Overall it did fantastic! Impressive power! BUT they don't have the weight to hold steady in high winds. I made two short trips in March that scared the heck out of me! Perfectly balanced load, weight distribution/anti-sway hitch and I was crabbing all over the fwy! One spot between Tucson and Benson I truly hate as you get 35mph semis in right lane and 85mph in the left lane...

That said I too did lots of research about ATF temps and most are on old technology where 220° was worry zone. New Tundra, which I bought lives about at 220°! Sounds crazy I know but I got a 100K warranty and I'll let ya know what happens along the way. Many other modern AT's run in the 220° range whereas my 2013 Tacoma was 165° and maxed at 185°

ATF fluid and coolers are tricky. Toyota claims too cold as much problem as too hot since it can always be too cool. My Tundra takes ~20 minutes flat 45-65mph driving to reach 185° which is optimal. So 20 minutes a day too cool....at least. That was Phoenix 90°+ days too...

At any rate I ditched my Scanguage! Was driving me nuts!

So far the Tundra is the way to go! Makes towing fun and I'm up a 7000 foot mountain with my rig today. Tacoma woulda made it but not as relaxing to be sure!

I'd not hesitate to use my 4000lb Airstream + Tacoma for short occasional trips but being full time RV it made sense to swap out.

PS LOVE the Tundra! Got the 2019 SR5 4x4 Off Road but it came with some Pro attributes which is kinda cool!

Thanks,

Aztex

 

The engineers are fully involved, too. They might know exactly what the truck can handle, but would be equally conservative in rating the capacity because they know some people will push and/or exceed the rated limits...just because. The lawyers are there after the fact to say "the engineers told you so".

Post some pictures of that rig, I bet it looks great. Taco's are good looking trucks, and there's no trailer prettier (in my mind) than an Airstream. Does yours have a Jackson Pollock painting on the ceiling over the bed?