The Story Of A Cummins Suburban (Lots Of Pics)

[pickup67man]

Love the idea of a diesel in an older Chev. Have a new Chev with a Duramax and an old Chev and like the idea of mixing the two.
I'd say you are 6500 lbs and 25 mpg.

[ldg72chevy]

What did you use for a speedometer? Doesn't the NV4500 have a electronic sender?

[mosesburb]

Originally Posted by gerfunken

I'll guess 7200 and 20 MPG.....

A fuzz high on weight, but close on mileage. My K30 DRW 6.2L with three full tanks of fuel was right at 7200lbs.

Originally Posted by pickup67man

Love the idea of a diesel in an older Chev. Have a new Chev with a Duramax and an old Chev and like the idea of mixing the two.
I'd say you are 6500 lbs and 25 mpg.

Now you are close on weight, but high on mileage. I guessed 6500lbs myself and we were both 80lbs off. It scaled right at 6420lbs and the first tank of fuel netted me 19.5 mpg. There was a 95mi round trip of highway driving on it. The next tank of in town and significant rush-hour traffic with a/c netted 16.6 mpg. My major problem is I have WAAAAAYYY too much gear. I did the math and *ideally* I should run 3.23 gears. Now I would not go that high, but I have a complete 3.54 D70 out of a Dodge with a Cummins, but I started investigating the cost of freshening it up and then re-gearing my D60 for the front and figured for that amount of money I can buy a bunch of fuel, so for now the 4.10s stay. A higher gear would make it more fun to drive though.....

Originally Posted by ldg72chevy

What did you use for a speedometer? Doesn't the NV4500 have a electronic sender?

For a 2wd trans, you would be correct. With the 4wd setup the speedometer is driven off of the output shaft of the transfer case so it has a cable just like stock. On slight side note, with my calculated guess of drive gear and driven gear I am only one mph off at 50 mph. I'll call it my awesome ability at estimation and calculation, but pure luck probably played as much of a role as my calculations did.

[jbclassix]

Unfortunatly if you want to keep the 14b the highest match gears you could use are 3.73s. I dont blame you on not wanting to use the Dana 70. I know it is a beef of an axle, but every one I have come across has been a PILE.

I had the same problem when I lifted my 6.5l 96. I wanted 4.56 gears and 35's for wheeling, but that made me tach out at 75 MPH and 16 mpg with propane. She could pull ANYTHING though! Have you consideded a Gear Vendors Overdrive? You could split gears for even better fuel mileage!