So, I bought my first travel trailer and...... questions...

Edit: Corrected to say S5 per Txexplorer - thanks!

The manual says to use S5 or below. On the transmission we have, S4 locks the transmission's highest gear in at 4th gear, which only uses one set of planetary gears in the transmission - it's basically direct drive output for less heat. 5 and 6 on our 6-speed AT transmissions are both overdrive gears and will produce extra heat.

I always tow in S4 with ECT on.

If you're doing a long pull and it's slogging, there's nothing wrong with tapping down to S3 and pulling that hill at 5k RPM.

One last thing, engine braking adds a LOT of heat. Minimize that downhill when towing.

 

I hear what your saying I just don’t see where it says that in the manual.

 

I agree with you. I have scanned the manual many a time and have not seen S4 for towing. If someone can find it and show me, i'd appreciate it.

I tow in S5 + ECT on. No issues in 20K miles of towing or so.

I will say there are some slight differences in the manual between years though. If you check I believe a 2020 manual, some of the terms and wording is different from the 2017 manual.

 

@Txexplorer You're right - my manual (2017 SR5 DCLB 4x4) in the glovebox does say 5 or below - exact same as what you have above.

If you want to tow in overdrive, go for it. I'm sticking with S4. Again, less heat in the trans since it's not an overdrive gear.

 

P2 mounted there as well, access to the manual lever is critical. Also helps to adjust the controller after your hitched- and check your boost levels - I find B2 is helpful anywhere I'm going to be in traffic.. otherwise I keep it no boost.

 

“One last thing, engine braking adds a LOT of heat. Minimize that downhill when towing.”

Not so sure of that, but i can tell you using the brakes on a long descent instead produces MUCH more heat, so much so that you can have catastrophic brake failure. I always gear down on steep descents whether towing or not.

 

Installation was as easy as everyone said. I chose to hang it below the dash and it’s out of my way completely and easy to reach behind and unplug when not towing.

Question.....should the side screws be tightened so unit is rigid in hanger or should it float a bit? Those screws are hard to turn and I wouldn’t want to over tighten.

edit.... here are some pictures but I can’t get them to post upright so you may have to stand on your head to get a good look.

 

These guys are computer whizzes, someone will flip it for you.....

 

THANKS MIKE!!

 

Being a class a truck driver for a living and having to towing this rented trailer this past weekend 60 miles to camp in the hills I feel it’s not safe at all. I have a brake controller and wdh and anything over 50mph and you can feel that the trailer is the one in charge of the ride. On flat road it pulls fine but a little uphill it won’t get pass 3rd. My rented trailer weigh 4,500lb dry and I feel the Tacoma is just too small for it. You won’t have the weight power and the necessary stopping power to control it in an emergency. It can tow but you have to consider the safety of you and all motorist around you to. If it’s just local and mostly flat roads then you’ll do fine but long drives I don’t think my transmission gonna last. If I were to ever buy one 3,500 is the most I’ll go to be safe.

 

It probably shouldn't float because it might vibrate itself loose. I'd back the screws all the way out and then retighten while holding the bracket in place. With the screws already started and you holding it flush, the bracket should be in place well the second time.

Worse-case, you can put some VHB tape under the mount. VHB tape is great, and can be used in addition to the screws if needed. Looks good though, glad you were able to get it done.

That's true.

I'm sure of that. Consider:

• The same amount of slowing force required to not accelerate the truck and trailer is the same, regardless if you're using disc/drum brakes or engine brakes.
  
• This slowing force is converted to heat by the truck brakes and the trailer brakes through friction, or to heat by the truck's drivetrain when engine braking through compression and friction.
• The heat produced is the same for both situations - remember the same amount of slowing force is required, so the same heat is produced in either case.
• If you rely on only engine braking for a long incline, you are expecting the engine and transmission to absorb the same heat as the combined truck disc brakes, truck drum brakes, AND the trailer brakes would be. That is a lot of heat!

Physics aside, the Tacoma does not come with a valvetrain or cooling system designed to modify valve timing to induce braking from compression. Semi trucks and some large tow rigs are engineered with a valvetrain and cooling system designed to do that.


You can gear brake in the Taco by manually shifting into a higher gear to keep the revs high, but it's outside the scope of the truck's expected usage. You need monitoring (scangauge or Ultragauge) and added cooling (additional trans cooler) if you're doing so when towing, or you will roast your transmission fluid from the added drivetrain heat. That's a fact.

I gear brake, but I have an Ultragauge and a second trans cooler inline with the factory cooler. I also drive really slow when towing - always below the speed limit, never above 65 (which is also explicitly a recommendation in the manual).


The key takeaway from the above (if you're still reading my ramblings) is that braking produces a ton of heat when towing. SLOW DOWN before long downhills when towing. More speed means more heat. If you slow down, your truck will get less hot as you have more unit time per heat unit dispelled.

 

No worries, another thing - these are pretty cheap and I've found made a huge difference to how our trailer goes down the road;

 

Mike, you use this instead of a WDH? Curious how you can to that decision

 

Nope, I use Both.
Ride-Rites are my next step.

 

I agree with most of that, but i feel confident the cooling system can handle the heat dissipation. Far more heat is generated under load going up the hill, after all.

I’ve had an old land rover with bad headgaskets and a plugged radiator that would overheat dramatically — never did it to me downhill though, even on the 2 hour descent from flagstaff to phoenix in August

 

@MESO made it! Go to the sale thread here or look him up on www.mesocustoms.com.

Here's what it looks like:


It makes the controller look factory and looks great! You also don't have to deal with accidentally kicking it or having things hanging off your trim panels.

 

It's jury rigged. I placed the bracket on the underside like this:

This prevents the controller from falling out and adds some stability.

This is a good temporary measure until you can order a custom panel to fit your controller. MESO customs makes a good one like I said in my post above this one.

Those have a long lead time so in the interim I think the way I had mine mounted would be serviceable for you.

 

That meso set up looks pretty sweet. Do you leave the P3 plugged in all the time? Doesn’t it draw on your battery?