Engine/Transmission (1998.5 - 2002) vp44

[KFranco]

Fuel psi O. K. Boost is fine. I have a stock 2002 5sp. Truck runs o. k. empty but is a dog when towing my 8000lb trailer. Truck will not smoke at all... (lack of fuel being injected?) No codes via the switch method. Can this still somehow be my vp44? Or am I missing something.

 

[Highfinance97]

You say that it wont smoke at all, what have you done to the truck that you think it should or would smoke???





Michael

 

[SNiebaum]

Stock trucks shouldn't smoke...

 

[KFranco]

Didn't realize stock trucks don't smoke. Just thought all diesels do to some degree. Still doesn't explain lack of power. Thanks for replying.

 

[SNiebaum]

What rear gears do you have?? What tire size are you running?? Do you have gauges?? What do your EGT's look like?? Are you still running the stock lift pump in the stock location??

Codes don't always show up with the key trick and not all dying/dead VP's will set a code.

 

[GDMRTN]

Stock power levels will not smoke or make power. Truck will always be a dog if it is stock. When my truck was stock I didn't even think of hauling/pulling anything. VP pump stock truck sucks imo. A good programmer would liven it up. Unless you have low fuel presssure or lack of fuel flow.

 

[KFranco]

have 3. 73 rear gears. only have fuel pressure gauge. didn't think I needed others with stock truck until now. I actually just ordered boost and pyro tonight. tires are 285/75/16. I have a GFS-391 fuel pump. I haven't dropped below 10psi

 

[SnoKing]

How did you get 3. 73 gears. Stock was 3. 56 or 4:10. Lift up on the throttle pedal and see how much it moves. Mine had about a inch or so of free play and was not openning the VP44 all the way. Used a split fishing line weight to take up some of the slack in the cable. Got a lot more power. SNOKING

 

[SNiebaum]

have 3. 73 rear gears. only have fuel pressure gauge. didn't think I needed others with stock truck until now. I actually just ordered boost and pyro tonight. tires are 285/75/16. I have a GFS-391 fuel pump. I haven't dropped below 10psi

A good set of gauges can be your best friend... . you can tell quite a bit about your truck watching the EGT and boost gauge. And we all know how important that FP gauge is.

 

[KFranco]

I only know what others have told me. Thanks for all the replies. With a search here I'm sure I can figure out what gears I have. Thanks again

 

[JKinney]

Ditto to all the posts here thus far. Boost leak????

 

[JFlagg]

Look in your glovebox, there is a label that will let you know what gears you have. If that doesn't work, what RPMs are you running at 70 mph? 3. 55s will be about 2000 RPMs, 4. 10s will be between 2100-2200. 285 tires will lower these RPMs about 50...

 

[Highfinance97]

Look in your glovebox, there is a label that will let you know what gears you have.

Also check under your hood or a label





Michael

 

[SnoKing]

Look in your glovebox, there is a label that will let you know what gears you have. If that doesn't work, what RPMs are you running at 70 mph? 3. 55s will be about 2000 RPMs, 4. 10s will be between 2100-2200. 285 tires will lower these RPMs about 50...

With 4:10's and 265, it is closer to 2300 at 70MPH. 65 is 2000 RPMs. SNOKING

 

[KFranco]

I definitely have 3. 56s I know 4. 10s can pull more weight but I'm only pulling 8000lbs... will this really make that much difference pulling this weight... it's just over half the weight this machine is supposed to be able to tow.

 

[SNiebaum]

I definitely have 3. 56s I know 4. 10s can pull more weight but I'm only pulling 8000lbs... will this really make that much difference pulling this weight... it's just over half the weight this machine is supposed to be able to tow.

Perhaps a better description of the issues... describe a scenario where the truck isn't performing to your expectations?? Will it maintain a constant speed when towing uphill?? Can you accelerate at all on flat ground with this load??

 

[KFranco]

While pulling the load listed I think it accelerates fine and even can maintain a constant speed of 40mph up a hill. As soon as I cross over the 45mph mark all of sudden the truck starts losing power. I can gain speed up to 65 on flat ground wot but as soon as any hill or slight grade comes it will lose speed quickly until it reach 40mph or so and then feel strong again. By next week I will have my boost and egt gauges installed and maybe I will gain some valuable input then. At the higher speeds the truck just sounds like a gasser that's missing real bad or like its running on 3 cylinders. Anyway, thanks for everyones input.

 

[mhenon]

While pulling the load listed I think it accelerates fine and even can maintain a constant speed of 40mph up a hill. As soon as I cross over the 45mph mark all of sudden the truck starts losing power. I can gain speed up to 65 on flat ground wot but as soon as any hill or slight grade comes it will lose speed quickly until it reach 40mph or so and then feel strong again...

It almost sounds like you're running in the "limp" mode. I had that happen when my VP was going south. Power just falls off once you hit the limit.

Something definitely isn't right there. Don't know why it's not throwing a code.

Mike