would towing a car that is roughly 2000# on a 200 mile round trip in overdrive be asking for trouble? it would be about 95-98% freeway in northwest washington state. i was also thinking that i could probably get away with using overdrive on the flat areas and take it out of overdrive for hills. any advice would be appreciated:)

If you find the transmission have a hard time hold gear or "hunting" then take it out of overdrive.

would towing a car that is roughly 2000# on a 200 mile round trip in overdrive be asking for trouble? it would be about 95-98% freeway in northwest washington state. i was also thinking that i could probably get away with using overdrive on the flat areas and take it out of overdrive for hills. any advice would be appreciated:)

The 4L80E is quite happy towing in Overdrive so long as it will hold the gear, and preferably, stay in lockup as well.

If you'll be able to do that or not depends on your gearing (3.73 or 4.11?) as well as the terrain. The terrain in WA varies quite a lot IIRC so you may have to vary your choice of gears to keep the tranny happy.

All that said, a 2000# car on a trailer that will probably weigh no more then 1500# (assuming a flat deck) totals ~3500#. You won't be stressing your transmission much no matter what gear you drive in, unless you have 3.42's or something and plan on pulling up logging roads. :)

FWIW, he's a pic of our setup in Washington state - Vantage, WA to be exact - I remember it like it was yesterday. As you can guess we weighed a lot more then you will be towing, and I towed that entire trip (>6500 miles) in overdrive.

http://gallery.me.com/oshawapilot/100049/DSCF1245/web.jpg?ver=13011428080001

Take it out of overdrive before you start hill climbs so it doesn't have hard downshifts after lugging with your foot dep in the gas. Overdrive will be fine for flats and downhills. If you are trying to save gas by using od just slow down while towing. That'll make the biggest impact

I posted my conundrum on another thread in this section but I'm still a bit confused. We have a trip to the river coming up and the climb up Chiriaco Summit on the E/B I-10 outside of Palm Springs here in SoCal is over 12miles,very steep, and only two lanes so you often get caught behind big-rigs,etc crawling up the grade. In years past I've always left the truck in T/H mode and just let the trans do it's job. Would I be better off towing in manual mode and doing the downshifting myself/would this help keep temps down? If I stay in T/H mode but also in manual will the TC stay locked up? I sure has hell don't want to limp this thing!! If I decide to just go manual and do all the shifting myself, my other question is do I have to back off the gas when I downshift or do I just keep my foot in it and downshift as needed? At this point I'm still figuring on doing it the way I always have done as stated above. I'm not the least bit concerned with mpg's as I am keeping temps down. Thanks for you input!!

IMO the only time you should need manual mode is if the transmission is hunting for the right gear, or in other words shifting in and out of overdrive very frequently.

If you have tow haul mode, let it do it's thing - the Allison is a pretty smart transmission.

It's only us 4l80e (or non Ally) guys that really need to worry about manually controlling the transmission user some circumstances while towing. If I had a tow-haul mode with the smarts of the Allison I'd use it and not worry about things.

Ok thanks..I just hate it when I have to try and get back up to speed after getting stuck behind a slow big-rig trying to pass an even slower big-rig and trying to get back up to speed..I thought if I was in manual it might not lug so hard when I start to get back on the gas as I try to get my speed going again. Thanks for the input!

Stay behind the big rig and watch your MPG skyrocket. That's what I do. ;)

15-25mph up a steep grade for 15+ miles behind a big rig!?:eek: No way..I could care less about mpg's..I wanna get up that hill!!:)

I tow at least once a week with the automatic transmission in my powerstroke. I never take it out of overdrive. I live out in the sandhills so you never use cruise. As long as you pay attention I would let it run in overdrive as much as it wants. Ive pulled 20,000 in overdrive with mine for a good 200 mile trip and never had any trouble. I have 4:10 gears though. Hauling cattle with stock trailer loaded that weighs around 14000 I usually dont even shift out of overdrive pulling through the hills.
Good Luck!