Recently I changed my oil and added Lucas oil treatment in the old 6.2 suburban in preparation for our Yellowstone trip. When I filled up I also added Lucas fuel treatment. Well I really have no idea how many miles are on the old boy but on the way up she ran really good until I would really get on it, then the "water in fuel" light would come on not to mention the general falling on it's face kind of feeling at higher RPMs. On the way back the old motor started sounding louder, I knew she leaked a little so I checked the oil and it was a little low but not bad. I have not ran any more of the fuel treatment in it since the first fill up so I am sure it would have ran it's course but it still falls on it's face at higher RPMs and the water in fuel light will flash sometimes.

I had put that Lucas Diesel fuel treatment in before and I do remember about the same results, but just figured it was water in the fuel. However, since then I hadn't noticed the general falling on it's face feeling or the light coming on until I added it this second time.

Has anyone else had similar experience with those fuel and oil treatments.

I have read a lot about you guys using 2 stoke oil for additives. I don't know what I need for sure. All I know is that I want more power, I want it to run cooler. I have used that engine Restore engine treatment before, and it does seem to help. What you guys think.

 

dump a quart of ATF in it the next time you fill it up see what happens then, should help everything, Lucas isn't so shiny for diesel fuel addative i don't think

 

I use a lot of Lucas fuel additive (I buy it in the gallon jugs) and have never had problems from using it nor has it caused the water in fuel light to come on or caused the engine to fall on its face.. I don't use 2 cycle oil as I lose mpg every time I have used it but being your have an older engine it may work.. Being that Lucas also works with gas, I use it in the wife's SUV gas tank with good results.. I would use Marvel Mystery oil before I would ATF as ATF has to many friction additive in it.. BTW when was the last time you changed the fuel filter? Also does the fuel filter you use also block water as some on the market do not and water is hard on injectors!

 

Sounds like a dirty fuel filter to me. I too run lucas in everything and have only had great experiences with it. Pull the filter and dump it into a clear jug and see what you have in it.

 

Well I tried a fuel dryer with about 10 gallons left in the tank, I tried to run it as low as I could before I refueled. After refueling, I added Marvel Mystery Oil in the fuel tank. I also added a can of engine restore in the oil. I flushed the radiator and filled it again adding Royal Purple Ice. Well pulling pulling my full 25 foot camp trailer up a two hour 4 thousand vertical climb it did alright, but much of the same that I described before was still prevalent. Oddly enough the vehicle sat for 42 hours with out ever being started, pulling home it was worse than it had ever ran. The water in fuel light was on most of the time and the general loss of power at rpm. Very saddened by the vehicle performance I began looking for other options for a tow vehicle.

Well the wife was going to take the vehicle to the mall, noticing a lot of oil like substance on the trailer and the suburban I started poking around and all the oil levels were good. The coolant level was a little low so I filled the reservoir and noticed it was leaking. Fixed that and wondered what the little square box was that was clamped down to the fire wall. Popped off the clamps and low and behold, a very heavy fuel filter. Got a new one and just drove it to work at full throttle the whole way with not water in fuel light coming on or loss of power. I am excited to hook up the trailer an pull the thing up the canyon tomorrow just to see how well it does.

Thanks guys... I didn't know the fuel filter was so easily accessed on these old beasts!

 

Bobcat67: That picture you have in your signature gets me going. I love mud, I love trucks and I love power!

I am trying to get my post count up so I can send a PM.
So I am a newbie to this diesel thing. But this really isn't just an expression to my diesel ignorance but just an expression of how everyday of my life goes.

So I filled the other day and did the math and my mileage was down another mile to the gallon or so. Rather disappointing, because I spent all this money to put this 700r4 in replacing the turbo 400, and fixed the leak in the fuel tank and before I spent all that money, I was getting around 15mpg. And the suburban I pulled it out of was getting 18mpg. I figured will a little tune up I figured I could be getting 19-22 mpg.
The mufflers over the last week or so have kinda deteriorated to the point that it actually sounds awesome, in doing so I have had a little heaver foot because it sounds so cool.
Well the math showed that I only got 13mpg. So.. a day or so went by and I realized that for at least 100 miles or so of that tank the speedometer had broke, thus the odometer hasn't worked either.