I'm ready to make a decision as to what is the best choice for towing with my b-van. B-van-1995 460 3:54 rear,banks trans command,E4OD transmission.GVWR 9600,15600 CVWR(18500 with the 4:10 rear) TT-Airstream 25 Excella GVWR 7300
Question is, do I install the 4:10 rear, or a gear vendors underdrive. Price is not the prime consideration. This is our fulltime set up.I know that gas mileage is much lower with the 4:10.I now get about 11 without towing.
I can put about 2000 lbs. in either ths b-van or TT and stay at the lower CVWR, but would rather have a better margin of error. Unloaded weight for the TT is 5840; For the b-van about 8000. All input is important.Time frame within the next 4 months. 314 days to retirement.
c u on the road
Harry
It depends on what problem, if any, that you are having. The main advantage of the 4.10 would be in getting the load rolling from a standing start. My unofficial gut feeling is you don't need it with that size engine and trailer.
The Gear Vendors Over/underdrive is actually just an overdrive. It won't give you lower gearing from a standing start. In fact it can not be engaged at less than 15 mph. The underdrive in the name comes from the fact that it lets you split gears, I.E a gear over first is also under second. I have a gear vendors unit, and it was the only thing that made my last tow vehicle acceptable. It will be on my 99 Dodge shortly but if you need a true underdrive i think you will have to look to U.S. Gear for a source. It would help you get the load moving and also fill in between gears. If I was ignoring cost I would rather keep the present rear end and get a few more gears.
My own vehicles are manual shift with a granny gear so getting started is not a factor.
Rick Davis 1602
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