i have a problem for my silverado :(

[the fall guy]

I have a problem on my silverado 6.5 td of 1996
my consumption is 20 liters for 100 kilometers
the silverado 6.5 td 1996 of my pere uses 13 litrers for 100 kilometerswhat is the problem? pmd? injectors? fuel pump??? other??
my english is bad, sorry, i' m french ;)
thank you for your help !

[trbankii]

Looks like you're getting about 12mpg while your friend is getting 18mpg.

First thing to compare is axle gear ratio between the two trucks. A lower gear ratio will give you more power, but less mileage.

[AlexFolino]

Also do some obvious checks, does your truck have a CEL on? How about maintenance items, tire pressure, etc..

[racer55]

Do you have a boost gauge?
Do you get a lot of black smoke when under heavy throttle?

[the fall guy]

the ratio is 3:73 for my silverado
the ratios is 3:73 for a silverado of my father
yes I have a black smoke during accelerations engrossments, thing which doesn't occur on the silverado of my father
she pressures of tyres am good (2.5kg-3kgs) air filter, fuel filter, oil filter is OK

[a5150nut]

Do you have a boost guage?

Try checking the plastic lines from the vaccume pump to boost solinoid and from solinoid to turbo. Also check electrical connection at boost solinoid.( on left vaulve cover)

Any codes stored?

And Welcome!

[twaddle]

Are tire sizes the same? Are the transmissions the same and are they operating correctly ie both going into overdrive/lock up?

Jim

[DennisG01]

The black smoke is a likely indicator that you're not making enough boost to burn the fuel (assuming everything is stock). Another easy check is, with the engine idling, try to manually move the wastegate arm. It should not move easily.

While that may be the entire problem, another thing to consider is driving habits. If after fixing the black smoke you're still seeing a noticeable difference, try switching trucks for about two tankfulls and compare again. It could just be that dad has a lighter foot.

[JohnC]

My father always got better mileage than I did, even driving the same vehicle. Something about driving styles... ;)

[jamesm]

Bonjour,

Does your truck have a "trap oxidizer" or "soot trap" or "diesel particulate filter" still fitted? It would be the first housing past the turbo downpipe in the exhaust system; it will look like a small "muffler" or exhaust noise suppressor.

If so, it may be clogged up, restricting air flow and resulting in your "rich"/smoky operation. I have read on the internet of some people taking the housing off, breaking out the interior pieces, and re-mounting the empty housing.