Towing up grades with "M" and 1 gears
So I have several coaches, but this will be my first attempt pulling a TT up a steeper mountain grade. I'm towing with a 1 ton Chevy express 3500. I'm a bit "confused" on just how to use this tra...
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Please ignor all the post that start off saying "just..." With towing you dont "just" do anything.
If you are driving flat ground then keeping it in D is fine, tow mode or not. Tow mode will change the shift points of the trans, and there is nothing different about how the engine runs, just the transmission. Trans will rev higher before upshifting is what you will notice.
Yes, very much DO shift the trans into a lower gear for those white-knuckle downhills. Use the engine to maintain slow speed, not the brakes. I assume you have a gas engine? diesel engines will have very little engine braking effect without a Jake brake or exhaust brake engaged.
Gas engines do have a lot of restriction when off the gas pedal and coasting, so is useful.
Now, what gear to be in depends on the speed you want to maintain, the grade and the weight of the trailer.
Without researching the info you did not give us on your specific transmission, lets just assume you have a 4 speed with overdrive (5 forward gears). 5th gear is the O/D and the highest gear. With O/D off the truck will not shift into anything higher than 4th gear, and coasting speeds will be slightly reduced. In 3rd gear the truck will not shift higher than 3rd gear (no 4th, no 5th) and downhill speeds can be greatly controlled until the grade gets steep or your speed need to be dropped way down for turns.
Don't wait until the revs are high before dropping down to 2nd gear (truck wont shift into 3rd, 4th, or 5th) as is harder for trans to shift down when rpm's are so high (high revs in 3rd means way higher revs in 2nd).
Whatever buttons or levers or trickery you need to do to put the trans in the appropiate gear needs to be well understood by you before heading out.
Start dropping to lower gears, one at a time, well before you think you need to. This is not the emergency plan or back-up plan. Lower gears is your first solution to long downhill grades.
Using the trans/engine to slow the vehicle will save your brakes. Brake fluid will boil quickly and your brakes will fade or fail if you rely on them to maintain speed. This is not a good feeling. After brakes fail the engine can maintain speed, but then you have no way to further slow or stop the vehicle until they cool down.
If you are driving flat ground then keeping it in D is fine, tow mode or not. Tow mode will change the shift points of the trans, and there is nothing different about how the engine runs, just the transmission. Trans will rev higher before upshifting is what you will notice.
Yes, very much DO shift the trans into a lower gear for those white-knuckle downhills. Use the engine to maintain slow speed, not the brakes. I assume you have a gas engine? diesel engines will have very little engine braking effect without a Jake brake or exhaust brake engaged.
Gas engines do have a lot of restriction when off the gas pedal and coasting, so is useful.
Now, what gear to be in depends on the speed you want to maintain, the grade and the weight of the trailer.
Without researching the info you did not give us on your specific transmission, lets just assume you have a 4 speed with overdrive (5 forward gears). 5th gear is the O/D and the highest gear. With O/D off the truck will not shift into anything higher than 4th gear, and coasting speeds will be slightly reduced. In 3rd gear the truck will not shift higher than 3rd gear (no 4th, no 5th) and downhill speeds can be greatly controlled until the grade gets steep or your speed need to be dropped way down for turns.
Don't wait until the revs are high before dropping down to 2nd gear (truck wont shift into 3rd, 4th, or 5th) as is harder for trans to shift down when rpm's are so high (high revs in 3rd means way higher revs in 2nd).
Whatever buttons or levers or trickery you need to do to put the trans in the appropiate gear needs to be well understood by you before heading out.
Start dropping to lower gears, one at a time, well before you think you need to. This is not the emergency plan or back-up plan. Lower gears is your first solution to long downhill grades.
Using the trans/engine to slow the vehicle will save your brakes. Brake fluid will boil quickly and your brakes will fade or fail if you rely on them to maintain speed. This is not a good feeling. After brakes fail the engine can maintain speed, but then you have no way to further slow or stop the vehicle until they cool down.
