hey everyone i am starting my first conversion i am dropping a 5.9 cummins 12 valve into my 1988 chevy single cab long box.
reading the other forums about conversions i have some questions about the clearance with the 12 valve under the hood and the way i am going to transfer the power to the wheels.

first question i have is will the body need a body lift to fit the diesel ?

i would like to mount a NV4500 to the cummins but i would like to now if there is a difference between the NV4500 found in a chevy and a dodge ?

and the last would be i would like to use the standard rad found in the chevy with a 350 what intercooler would be the best fitting and possible fit in the front sub frame without and huge modification ?

like i said this is my first cummins conversion and if anyone would have any advice it would be greatly appreciated thank you

 

Other stuff you will run into are

the clutch master and slave... use the dodge stuff.. just use the chevy push rod from the clutch pedal..

motor mounts ... there are vendors or you can make your own.. most use the first gen dodge motor mounts and fab brackets..

turbo down tube clearence,, either use a low mount exhaust manifold or relocate some of the a/c stuff because it will be too close...

fan and fan drive .. the first gen dodge fan drive gains you about 1 1/2 inches in the front and works well..

power steering pump,, if you get a hydroboost truck its easy..the hoses just bolt up.. vacume brakes require a vacume pump and power steering pump from a pre 95 cummins motor... its easier to go hydroboost for brakes..

thats all I can think about right now....

 

I've heard a few people say the chevy clutch master has trouble with the dodge drivetrain... (1 guy I talked to used chevy master to dodge slave and said it's hard to get into gear) why is this?? dodge and chevy both use the same transmission, is it just the heavier clutch from the dodge??? I only ask because i want to have a bolt on master (chevy) so I don't have to fab my firewall for the twist-in style master (Dodge)

 

I am trying to do something similar with a 94 suburban with an NV 4500. Trans Action from Sun Valley, California is one of your best friends. Talk to Brad and tell him Ed referred you. My set up used the back of a Chevy set up and the front of a Dodge diesel, including housing, clutch, pressure plate and shaft and the tranny had to be built specifically for my need. (818)504-6262 or 6336.
Good luck.

 

the reason is that the piston in the clutch masters are different sizes.. the chevy is smaller.. so using the chevy master and the dodge slave cylinder causes the clutch not to disengage all the way.. if you want to go cheep the mid 90's fords had a clutch master that is the same size as the dodge... you just have to make a hose...

the southbend stuff is really good and what I am running its worth the extra money IMHO or just use the 160$ combo from napa.. if they want more find another napa taht will sell it at jobber prices.......

 

Yea...I did some research after posting that. Guess I should do some looking before i open my mouth again But I got the same answer you gave. Thanks for that! I also found out you can use a slave cylinder from a 94-97 jeep 4.0L and it bolts right up, that way you don't have mod your firewall or anything. Not sure if the lines are the same or not

 

so i am starting on the running gear of my chevy cummins and i am using a one ton setup out of a 1994 chevy suburban. the gear ratio i have so far is 4:10 but i have replacment diffs with 3:7:3 gear ratio. and i have a NV4500 out of a chevy one ton and the front mounting plate has been changed with a chrysler mounting plate.

 

Ya stay away from the 4:10 unless u r running 40" tires and I used the stock 89 chevy blazer radiator and it works great it was like 100 degrees out today and I was running the ac all day and intercooler I went with one off of eBay it was 31"long 3" thick 12" tall and it was like $90 or so and good luck you won't regret the build when your done

 

My 92 dodge has 4.10's with a getrag360 similar to a nv4500,, its great towing.. but top speed with 31's is about 80.. and to get over 20mpg you have to stay about 60mph anything over that and the mpg starts to fall. here is a good gear calculator

Gear Ratio Calculator

Try and keep your cuise rpm under 2k, the motor is most efficent at about 1750rpm.. mine worked best as a daily driver with 35" tires but towing with them sucked due to sidwall flex.. I tow heavy 12- 15k..

Now my crew cab has 3.54's in it but alot more hp, so i just tow in 4th but also can cruise empty at 70mph and still get good mpg it has 32" 225/70/19.5's on it..

use the gear calculator and try and work a combo that keeps you under 2k rpm towing and cruising.. good luck..

also if you are looking for a mileage combo with small tires the early non overdrive dodges came with a dana 70 front and rear that had 3.08 gears in it.. works great in a 2 wheel drive with small tires and a overdrive... 24-25mpg consistanly on the highway.. rember that larger-wider tires worse the mileage....the 35's cost me 3-4mpg..

 

I got 37" with 4.10 and get 20mpg wish I had 3.73 though