Towed in D instead of S4

Hello,

I recently towed about 2000 pounds including trailer about 250 miles with a number of long hills.

I left the truck in D instead of using S4. Do you think I did any damage to the transmission? Should I get the fluid changed earlier than normal?

Thanks,
Zach

 

No reason to worry

 

You are good.

 

Yeah that ain’t nuthin’
Hell, if I was on flat land with little to no headwind, and I wasn’t getting constant downshifts, I’d be trying S5 and D at that weight.

 

nah, i doubt it went into overdrive much anyway with all that weight combined with hills

 

Part out??

 

The truck is totaled, time to replace it. Actually this isn't good. Should of used S5 and S4 for the long hills. I would think if your engine temp gauge showed to be excessive, the transmission fluid would be to. At any i would go by what the manual claims for aft replacement anyways. I'd change it much earlier.

 

I'd ignore this ^^. You're fine, no worries.

 

The truck was in the midrange rpms most of the time. Going up the hills it was around 4500rpms at times.

 

Transmission knows what to do even when drivers don't. No issues op.

 

Did your trans oil temp light turn on? If not, don't worry about it.

 

Nope.

 

that's good. it should be in the high rpm range when towing. you don't want to be lugging around with a bunch of weight in overdrive.

 

Going up hills in D and pulling a trailer, your trans wasn’t in 6th gear anyway, so really not much different than S5 or S4 anyway when you were climbing. Still good to use S mode when towing or loaded down, but you didn’t hurt anything. And considering all the guys on 35s, with full skids, sliders, bumpers, winch, camper shells, roof top tents, and have their trucks loaded down with every piece of gear known to man at all times, I guarantee many of them are cruising around in D a lot too.

 

That means it knows when to downshift.
I think that you're fine.

 

No

 

Trust your Nannie’s. Toyota engineers might know more about transmissions than the rest of us. Despite often claimed wisdom on this forum, there is likely no reason to use D when towing. The one thing to be aware of is over use of the brakes when descending long slopes. Use s-mode engine braking to prevent the brakes from over heating and also your alternator from producing too little electrical power if your trailer draws a lot of power

 

You’re totally fine OP. I do this more than most people here would ever recommend. Toyotas transmissions aren’t stupid enough to kill themselves. Hell, s4 or not mine usually just sticks with 4th towing anything over 1800lbs.

 

Lol that reminds me of the time my father pulled his 3500lb boat and trailer up a boat ramp in 4hi and forgot to disengage until he got back home, 200 miles away. I don’t know how he didn’t notice it, but it was raining and mostly at highway speeds. In any event for the remaining years he had that truck, nothing bad ever reared its head. It was a 2003 Off Road.

 

I thought I felt a disturbance in the Force...