Hello all, seeking experienced advice. I just purchased my first Diesel Truck. 95 2500. Seems there is no using electronics for improvement, so I need mechanical advice. Looking to improve MPH. NOT looking to increase the power. I was told intake and exhaust. What would be suggested, brands, sizes, and any thing worth doing. I use it for hauling, the camper, wood, skidsteer and whatever else I need. All advice is greatly appreciated. Thank-you

 

Do you want to increase speed or economy?

If speed- get a governor spring kit- this enables the engine to rev higher, in stock form the engine will start to reduce torque output above 1600 rpm, and be flat on it's face at 2500 rpm.
With a governor spring kit you can lift your usable power band up to 4000 rpm, but this needs some additional modifications of the engine.
Intake and exhaust mods- well with stock power the stock components are OK.
A better flowing air filter like the BHAF (big honking air filter) is a cheap and reliable modification. (search for BHAF on this site)
A 4" exhaust helps a tiny bit, but mainly because it gets loud and you drive slower
If the stock exhaust is still on the truck take a good look for loose baffles in the muffler- they will plug the exhaust and make the truck slow and thirsty.

If economy-
Start out with the absolute basics- valve clearance, air filter, oil etc- then maybe check your injection timing.
Depending on the wear on the injectors (mileage and fuel quality for the last 22 years) it can prove worthwhile to change the injectors.

Do yourself a favor, and get gauges- EGT (exhaust gas temperature) is a must, for automatic transmissions a temp gauge is highly recommended.


Another reason for low power and bad fuel economy- the fuel lines from the tank to the lift pump. If they are porous they suck in minute amounts of air and make the engine run badly
HTH

 

Get a tuneup on your right foot - driving style has a lot to do with fuel economy. I try to keep boost at/under 5psi when accelerating (I know you can't do that with a trailer on, but you can when running without). Coast up to traffic lights, instead of running up and then braking hard... All that kind of stuff will make a big difference in fuel economy.

 

Bump injection timing to ~16°, free flowing exhaust. I personally don't see a need for a new intake with stock power, but it won't hurt at all.

Some say a 190° stat helps with economy as it runs a bit warmer, my truck didn't like it though so who knows. Stock is 180°.

Other then that, stockish size tires are best for towing, switching oils to synthetic (axles and engine) might help a bit.

 

Another thing, keep your engine RPMs below 2000. They lose efficiency quick above 2K.

I like 1650-1800 the best.

 

I'm seeking economy, not so much the power. I don't want transmission problems. The truck has 300k on it, so I don't want to stress her......

 

I drive a big truck, so that I do second. Nature.... With my car's also...

 

I am looking for stock rims, the last owner had 17's. As per the thermostat, my parts dealer only can get a 180° , as I already installed and flushed the core and system. I shall consider moving the timing to 16°, but not sure what free flowing exhaust means. Brand?? And what size???

 

As a 18wheel driver, I do.... Thks

 

Ok, what kind of MPG are you currently seeing, is it an Auto or 5 speed, and what is your current climate ( cold, warm, etc. )

We can dispense with some of it as you already know about winter fuel mileage versus summer...........

 

I'm getting 17.5 just driving to work. It's a auto. I live in PA. I am familiar with the different types of blends.