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Old Oct 14, 2005 | 10:45 PM
  #1  
mono570's Avatar
mono570
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Trailering
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Hi there... This is my first post to the site so please excuse my ignorance if my upcoming questions were already answered in a previous thread...
Last year, I acquired my first truck, a Ford F250 Lariat, Super Duty 7.3 L Turbo Diesel and I just love this Vehicle!
Until recently, the truck has been running great but I've noticed a few things that are beginning to concern me. With that in mind, I talked with a couple of mechanics I had used in the past regarding the situation but they seem stupefied with the workings of a diesel engine; which brings me to this forum... Hope you can help.
1) Every 3000 miles, I leave the truck in for oil change; every 6000, I change the air filter and fuel filter. Is there more maintenance I should be performing to keep the truck running in good shape?
Currently, there is 81000 miles on the clock, I purchase the truck with 62000 miles.
2) When I purchased this truck, I was getting 16 MPG but just over 1 year later, MPG has dropped to 15.5. What causes the drop in MPG? Can I have the engine decarbed like a gas engine or is there a similar method of removing buildup?
3) I notice a heavy blast of smoke as I accelerate on the freeway. This happens mostly as I leave cruise speed to overtake a slower vehicle. A black cloud of smoke is clearly visible in the rear view mirror as I put my foot down on the accelerator. I don't remember this happening when I first purchased the truck.
I don't know if all these problems are related to the same issue, if there is a step I'm leaving out in the routine vehicle maintenance, but any info you offer will be greatly appreciated.

Regards
Nick
 
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Old Oct 14, 2005 | 10:56 PM
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Medic 66
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Do you use any DFA?
 
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Old Oct 14, 2005 | 11:01 PM
  #3  
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RAMPAGE_F350
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Joined: Aug 2005
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From: Central Alabama
When did or have you changed your fuel filter? Get some DieselKleen additive (grey bottle) from walmart. The smoke is unspent fuel. If you have the stock air box, I recommend doing the Kwik Filter Mod(fleetfilter.com #46637) the best $18 you will ever spend. The other guys will chime in, good luck.
 
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Old Oct 15, 2005 | 11:37 AM
  #4  
mono570's Avatar
mono570
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Trailering
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Rampage_F350... Thanks for the info. I change the fuel filter every 6000 miles. I'll add the additive and see if that helps.

Medic 66... What's DFA?
Regards
Nick
 
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Old Oct 15, 2005 | 11:53 AM
  #5  
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chapguy
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DFA = Diesel Fuel Additive....aka Diesel Kleen, etc.
 
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Old Oct 15, 2005 | 12:01 PM
  #6  
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LONEPINERON
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Joined: Jul 2005
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From: BC Nevada
Diesel Fuel Additive, Also you did not say anything about using coolant additive, real important for these engines. Are you having the work done at ford? If you change out to the 46637 air filter you may cut some of the black smoke down and will feel a slight boost in performance. Also throw some Diesel clean in every tank it will keep your fuel system clean and cut a little of the smoke. Changing your fuel filter every 6k seems a little excessive. But if that's what makes you happy great. I change mine around every 15k and have never had a problem. As far as the mileage goes that sounds about normal. You have stick or auto. Also I have noticed in last couple of years the fuel isn't as good in California. Mileage just went down but back up in other states. Hope this helps. LPR
 
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