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| | | | Joined: Jan 2008 Posts: 23 Apprentice | | Apprentice Joined: Jan 2008 Posts: 23 | Hello all... I bought my COE at the Daytona Turkey Run in November, and have been working on it ever since. Glad to have found this forum, for it looks very active, and I like your attitude.
My truck had a 292 c.i. straight-6/TH350 when I bought it, but I have a 6.2L diesel ready to drop in, along with a TH-400 transmission. The truck has 5.29:1 dually rear out of a '97 Chevy box van, along with the front end from the same van, so disc brakes all around. Does anyone think I will need an overdrive unit to get decent mileage on the road, if I use it to haul a car trailer?
I'd appreciate your input. Thanks!
~Bruce
Last edited by oc51; 01/24/2008 2:24 AM.
| | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | Welcome to the Stovebolt!
Seems to me most the overdrive automatics are not supposed to be used in overdrive when towing. There may be some exceptions, but I'd check into that before making a change.
It may also depend on what you mean by decent mileage. This is a big box you are pushing through the air. Its not going to get great mileage regardless of gearing.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jan 2008 Posts: 23 Apprentice | | Apprentice Joined: Jan 2008 Posts: 23 | If I do go with overdrive, it will probably be with an Overdrive/Underdrive unit, so I can multiply my gears on the road. I'm just not sure how stout these units are when towing a car trailer. 12-15 mpg would be acceptable mileage for me, since the truck more resembles an anvil than a jetliner! (I AM a little dismayed by the cost of diesel fuel nowadays...used to be cheaper than gas, but then I guess you have to pay for that "box-of-bolts" sound!  ) | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | That being the case of the choices you've listed the TH400 is the best answer. However there are better automatics for heavy duty use.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | |
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