I have an '85 van with a C6 transmission 4.1 rear end.
-I want more torque at the wheels from a stop (7000# trailer on a steep mountain dirt road; this would only happen a couple times a year)
-I want better fuel mileage (overdrive)
-I want to be able to haul a heavy load over a mountain pass without the transmission overheating (I haven't done this yet).
-More engine braking ability for steep mountain passes with a heavy trailer.
-It would be nice to have an automatic for the sake of others who may drive the van but not necessary.
These are the options I've thought of so far:
4x4 C6 w/ transfer case. Regear rear end to 3.? I would like it geared higher than 3.5. Is 3.0-3.3 an option? Can I get a limited slip or locking differential this gear range?
Question: If I have it geared at 3.? and I need to go over a mountain pass and 1st gear isn't cutting it will it damage the transfer case to run it in 4 low for 40 miles?
Question: Will a transfer case fit under the van without major modifications? I don't mind moving a crossmember but would rather not modify the floor too much.
4x4 Zf5 w/ transfer case. I can get two parts trucks both with 4x4 zf5's in them for $600. The downside is trying to modify the van to have a floor shifter with a bench seat in the front. The other downside is it will be less drivable for my wife and mother-in-law (they still can).
Medium duty manual or automatic transmission. This has the additional downside of many unknowns. I can mount up a zf5 and I know the clutch and flywheel will work. I don't know what I'm getting into if I go the medium duty route.
Question:Is it possible to get the gear spread I want?
C6 with aux transmission. Possibly regear rear end if I can't get an overdrive of 0.7-0.8.
Budget and time are a concern here
How much does a budget conscious limited slip or locking differential cost with 3.? gears on it?
Any thoughts? Is is even worth looking into a medium duty automatic transmission? If I'm going to go that route I would want a lock-up Torque Converter with overdrive and a big gear spread.
How much do aux transmissions cost?
-I want more torque at the wheels from a stop (7000# trailer on a steep mountain dirt road; this would only happen a couple times a year)
-I want better fuel mileage (overdrive)
-I want to be able to haul a heavy load over a mountain pass without the transmission overheating (I haven't done this yet).
-More engine braking ability for steep mountain passes with a heavy trailer.
-It would be nice to have an automatic for the sake of others who may drive the van but not necessary.
These are the options I've thought of so far:
4x4 C6 w/ transfer case. Regear rear end to 3.? I would like it geared higher than 3.5. Is 3.0-3.3 an option? Can I get a limited slip or locking differential this gear range?
Question: If I have it geared at 3.? and I need to go over a mountain pass and 1st gear isn't cutting it will it damage the transfer case to run it in 4 low for 40 miles?
Question: Will a transfer case fit under the van without major modifications? I don't mind moving a crossmember but would rather not modify the floor too much.
4x4 Zf5 w/ transfer case. I can get two parts trucks both with 4x4 zf5's in them for $600. The downside is trying to modify the van to have a floor shifter with a bench seat in the front. The other downside is it will be less drivable for my wife and mother-in-law (they still can).
Medium duty manual or automatic transmission. This has the additional downside of many unknowns. I can mount up a zf5 and I know the clutch and flywheel will work. I don't know what I'm getting into if I go the medium duty route.
Question:Is it possible to get the gear spread I want?
C6 with aux transmission. Possibly regear rear end if I can't get an overdrive of 0.7-0.8.
Budget and time are a concern here
How much does a budget conscious limited slip or locking differential cost with 3.? gears on it?
Any thoughts? Is is even worth looking into a medium duty automatic transmission? If I'm going to go that route I would want a lock-up Torque Converter with overdrive and a big gear spread.
How much do aux transmissions cost?