plc...@aol.com
1998 Dodge Ram 2500 QC 4x4 Cummins 5sp 3.55
PLCPRO wrote in message <199806192315...@ladder03.news.aol.com>...
We have a 1997 Dodge Ram 2500, 4x4 Cummins 5sp. 4.10.
We were turning 2000 rpms at 60 mph. We installed a Gear Vendor
Overdrive/Underdrive, and now we are turning 1500 rpms at 60 mph. We now
get 20-22 miles per gallon of diesel.
The truck runs much quieter. You can actually hear each other talk.
It cost about $3200, but has been worth it.
With the Overdrive and the Bf Goodrich Velvet Rides that we installed, the
truck now rides like a normal vehicle. My daughter no longer calls it "the
Semi".
Diana
Yes...you have an overdrive transmission. the Overdrive NO is probably
related to the OD switch used with automatic transmissions.
> Why is it that people with older 12v trucks seem to get better milage. Is
>it the 5th gear ratio.
no idea
> Under the hood the sticker says I have a Dana 80 rear axle but does not
>give the waight rating. I would like to know what it is.
it's on the door sticker...it'll be 6084lbs GAWR due to the tires, not the
axle
> My manual says this about shifting." For improved clutch life, all five
>forward gears should be used. For steady highway driving with light
>acceleration, 5th gear is recommended." also "You should use low gear when
>starting from a standing position if under a heavy load." It is now wonder
>people don't know what gear to start in, one place the manual says to allways
>start in first, in another place it says you only need to start in first if you
>have a heavy load.
their owner's manuals are horrible...and full of mistakes. Look at the shift
points (speeds) for acceleration vs cruise...they're reversed!
> Why was I charged $100.00 for a shift on the fly transfer case when it is
>standard equipment.
That's the heavy duty transfer case. It's a good thing
> > Why is it that people with older 12v trucks seem to get better milage. Is
> >it the 5th gear ratio.
I would be curious as to what Dodge tells you the reason is. As far as
I am concerned, the reason is that the 12 valve has a base compression
ratio of 18.5:1 while the ISB's base CR is 17.3:1. What that means you
can find in any good thermodynamics book, and I seem to have lost mine.
But as I recall it went something like,"the higher the compression ratio
the higher the efficiency."
Kent
>