Re: [VAL] Towing

["Uwe Salwender" <salwender@xxxxxxxxxxxxx>]

Barb,
I tow with the very same truck, although a lighter trailer. Formerly a 
1971 Tradewind, and soon a 1963 Overlander.
The tow rating for your Suburban is around 6000lbs, providing that you 
have the factory tow package and at least a 3:73 differential. If you 
don't know if your Suburban is properly equipped for towing, then visit 
your Chevrolet dealer and have them print a build sheet, which will 
have all the options listed by codes, and then they can tell you which 
differential, tow package etc. is there. Also, with a combination like 
yours, I suggest a trip to a public scale, to get the exact trailer 
weight, fully loaded for a trip. I would not be surprised if you're 
closer to 7000lbs than 6000lbs.
I towed my 5800lb Tradewind over the rockies last year, and although it 
got a bit slow at 9000ft+, things went well, and I never slowed down 
below 30mph on tight passes and curves. I would not have wanted another 
pound in the truck or trailer, though.
To your question: Do not tow in OD with this truck. Especially not in a 
overload situation, which you are approaching. Tow in "3", even though 
there's a overdrive there, too.
I always leave it in "3" when towing, with very few exceptions, like 
long flat or gentle downslopes with no headwind. It makes hardly any 
difference in mileage, but does save your transmission from slipping in 
and out of overdrive, thus eliminating excess heat and premature 
failure. The torque converter lockup is necessary to keep the 
transmission cool, which does not happen in OD with a heavy load. 
Slight slippage can occur, unnoticed by the driver.
Best,
Uwe Salwender
Orange CA