Engine/Transmission (1994 - 1998) mpg woes, somethings not right

[mbarrick]

I have a 97 3500 4x4 dually 5 speed 4:10 gears with an over drive unit, also 60 horse injectors, #10 fuel plate, 191 delivery valves, 4 k gov springs, timing set to 16*, stock turbo, exhaust brake, 4" dual exhaust, K&N cone air filter. I've only had this truck about a year and only get around 13 mpg around town and maybe 9 when towing my gooseneck trailer. The trailer weighs around 14,000 lbs but this is getting ridiculous, I just don't understand whats going on. Can anyone give me some insight? Also I had this same exact setup on a 95 2500 automatic truck and got about 17 and 12 when towing.

 

[Vaughn MacKenzie]

Mileage doesn't sound that far out of line to me. Think about this, my '98 2-wheel drive shortbed only gets about 12 towing my 20-foot travel trailer which weighs far less than your gooseneck. Last weekend it only got 9mpg the first part of a trip but I was bucking a headwind for a little while then climbed Cabbage Hill. I think my flyweight '98 is doing worse than your big 4x4 dually.

 

[bmoeller]

Get a better breathing turbo. The difference in the O/D ratios make you spin higher RPMs with the handshaker vs the auto, and the stock turbo is VERY restrictive. I picked up 1. 5mpg going from the stocker to a used PDR HX40. I wouldn't recommend that turbo for your use, though. The HTT turbo I have s a MUCH better turbo.

Your mileage isn't really out of line. I get 14 in town and 10 with a trailer. Before I installed the flatbed on my Ram, I was getting 15-17. 5 empty.

 

[mbarrick]

I do want to upgrade the turbo, I was thinking about going with a used hx40 that a guy I know has. What else would be a good turbo for my heavy towing use without breaking the bank?

 

[hsmith]

So far, I am liking my Super B. Will be headed to NM in July then will know for sure. I pull a fiver at 14k empty.

 

[bmoeller]

The HX40 is ok, but I don't recommend it. Particularly in stock form. They're cheap, but far from the best. Could never control the smoke and EGTs with it towing. The HTT I can.

I'd get a HTT 62 or 64/14. Or, if you have the cash, get the SS 13 housing.