Keeping overdrive off on highway?

[pete_dc6]

In a couple weeks I will be driving about 1,300 miles in my 2002 automatic corolla. In addition, I will be towing a utility trailer with my stuff in it. I would guess around 700-800 pounds for trailer+cargo.

I've taken the car out with the loaded trailer, and it is slow to get to around 55 mph, but doesn't have too hard of a time keeping it there. Slight hills are definately a problem, and the transmission quickly downshifts.

I'm wondering if it would be easier on the tranny, instead of having to constantly shift back and forth, if I just kept the o/d off the entire time. It will run about 3200-3400 rpm. For the note, I plan to install a separate transmission fluid cooler as well. What do you all think?

[PhatRoyale]

A transmission oil cooler is definitely a good idea.

Turning O/D off on slight uphills is a good idea. But keeping it off for a long period of time might cause the car to overheat, to avoid damaging your transmission, turn it on whenever you drive on level ground.

[lt1tyrell]

Just my opinion but I would def tow with od off. The engine reving a little higher will be just fine. OD is not meant for towing with any vehicle really, especially a light duty car. You can drive 60mph no problem in drive. But again, just my opinion.

[Bitter]

if needed even downshift it to 2 when going up a hill, 2 ends around 60 or so you'll be fine if you need to crawl a steeper hill at 45 with the hazards on in 2nd. personally if you'll be doing this more than once, get a uhaul and rent a wheel dolly and tow the car and pack the truck.

[burnout8488]

Originally Posted by lt1tyrell

Just my opinion but I would def tow with od off. The engine reving a little higher will be just fine. OD is not meant for towing with any vehicle really, especially a light duty car. You can drive 60mph no problem in drive. But again, just my opinion.

Yes, but as PhatRoyale said, turn it back on when you're not climbing any grades. It'd be a waste to be turning 3400rpm on flat ground. You'll be running hotter and using more fuel for no reason.