I have owned a 1992 dodge Cummins,auto, 4:10 ratio cab and chassis since new. Did not know about this type forum in those days. My son still owns the truck and uses it in construction. Has 10 ft flat bed. Average milage is 15 mpg hwy empty at 8,000lbs. 10 mpg at 21,000 loaded pulling loaded trailer. ( no weight police please) Just a dog on take off but will produce power on a dyno at full throttle. I had purchased several dodges for a fleet I managed and was happy with their fuel milage. 19-20 mpg with heavy service bodys and variable traffic conditions. Dodge and cummins worked on it when new and adjusted the timing. It just acted like it may be a tooth off on the cam gear. Many years and 350k, later just resigned to it. Any ideas???

That doesn't sound off to me with 4.10s. That's what my 97 215hp 5sp got, mileage-wise. It just got there quicker!

You got to remember the 1st gen was a 160 HP engine if I remember correctly. 160 HP get consumed rather quickly pull heavy loads. Now as for the VE pump its a dynamic timing pump but has a few sensors that control the advancement. Might want to check over that and see if the timing is correct and the timing advancement hardware is all hooked up and functional.

Yea, tried all that when new. Even put a splitter box behind tranny that gave me a double overdrive with no help on milage. It did give me a gear slit for the Grapevine grade. 42 mph in second over. Made 2 trips across US with my 5r at 19,000 lb combo. The most I ever pulled up the Grapevine was 24,000 gcw. Thanks for this wonderful forum and the come back.

This does not sound bad to me either. I actually think it should work perfect. Regards Rod 6.4 DPF Delete

OK got my old dog back and have time to play with it. Watched video about replaceing governor spring with a 3200rpm spring and fuel rod from BD, and cranking down the star wheel 1 and 1/2 turns CW and advancing the timing 1/8 inch turn. What are the draw backs? Is the BD rod that much better than turning the stock rod 90 degrees CW. The BD spring and rod is $147.00. E-bay has the spring alone for $35.00. I remember working for $.50 cents per hour, bear with me.

Here what I can tell you.

 

3200 Governor spring

BHAF

Straight pipe 4"

Custom cut fuel pin

HX35W turbo

 

Is worth about 224/571...

http://forum.mopar1973man.com/index.php?/topic/4622-relentless70-dyno-run/

I saw a 4 different fuel pins in another post. Can you elaborate on the pin you used? How does the BD pin stack up? Who else supplys them?

you really dont need to go buy a whole new fuel pin. you can cut yours with a new profile to enhance fueling and save yourself the $100 bucks.

Keep in mind, the 4:10 ratio is not ideal unless you run rubber with larger circumfrance.  My rig has the optional tire size and seriously, at highway speeds, it's I'm wishing for another gear.  And I'm a second gen with more power than you.  A taller tire would reduce your pulling power BUT also give more distance per rev.  What was the stock ratio back then?  I find the stock ratio is pretty much best for typical use...  was sold a bill of goods when I got one with 4:10s.    

I bought 4.10 because this cab and chassis was a flat bed truck to haul 6,000lbs of bee hives and a 1000 lb crane. Many times we would drive back into wilderness on forest service roads. (Back to the power mod). I installed a 3200 rpm gov spring and the BD fuel pin. Advanced 1/8 inch on timing and 1/2 turn on star wheel. HX35 turbo with waste gate locked shut. It is now a barn burner. A little smoke at first pedal mash. Will hook up that 12,000 lb 5r and try a hill to see what kind of boost I get with waste gate locked shut and EG temps.

 The air line from the manifold that supplies boost pressure to the diaphragm controlling the fuel pin on the injection pump is just pressed into the housing. Mine just fell out while I was modifying the pump. I reset it with lock tight. That loose line could cause the fuel pin to lag and cause low power. Just a thought.