Yes another "towing w/ OD" question. Please look

[brianjwilson]

Thanks for looking, I hate these threads as much as you do!
Generally I always turn overdrive off when I tow, but I regeared and I'm running pretty high rpms. 4.88 gears with 33" tires.
In overdrive:
60mph = 2250 rpm
70mph = 2650 rpm
75mph = 2850 rpm
Overdrive off:
60mph = 3000 rpm
I'm planning on towing a 6x12 enclosed trailer up to Seattle (couple hundred miles on I-5, mostly flat. The trailer is roughly 2000lbs.
What do you all think about leaving it in overdrive and running 65ish?
If I run with overdrive off, it's 60 with the engine screaming (sort of).
I have a transmission temp gauge now (scangauge). Does it seem like using overdrive will be okay as long as the transmission isn't hunting and the temp isn't high? Or should I be worried about using overdrive at all, even if it doesn't work the truck hard?
Thanks for the insight!

 

[rwenzing]

You can leave the overdrive on unless you have shift hunting issues or need the engine braking.

 

[brianjwilson]

Thanks Bob!
Automatic transmissions are still a mystery to me, and I had heard that overdrive is a weaker drive gear and will develop problems if used much at all while towing.
While I was leaning towards what you said, I still had to ask.
Thanks again

 

[CDW6212R]

Ditto, the OD is a band of thin steel wrapped around a drum. It doesn't hold as well as other gear clutch packs. The load on the trans is what you worry about. Hauling up hill with a lot of throttle is hard on the trans. On flat roads with very little throttle, OD is not a problem. Try to avoid going over say 30% throttle while in OD, knowing that the trans would shift by itself at say 40%. Drive it by feel, if it seems free, not loaded hard, then let it stay in OD.

 

[brianjwilson]

Good deal, we'll see how O/D feels, though I think it will be fine. I've contemplated picking up a manual trans for the sport trac but I wasn't really impressed with the mazda 5 speed anyway. Notchy shifting with a tall first gear, a weak clutch, and problematic hydraulics. Not to mention the extra slop in the shifter with the body lift extension.

Thanks again for the thoughts.