In my 85 Ford E350 6.9L diesel with ATS 085 turbo, C6, 4.10 Dana 70, about a 27-30ft Class C motorhome, it has dual tanks. I thought the rear was larger, due to new aftermarket tanks being 22 gallon, but it didn't turn out to be. It might be 1 gallon larger at best vs the front tank. My tank selector valve leaks badly when set to the rear tank, so I bypassed the valve when I replaced the leaky, rotten old fuel hoses. It's plumbed directly to the rear tank right now, not using the tank tank at all. It had been been on the front tank only for I don't know how many years. I ran it that way for a good 9 months at least too, until I decided to use the rear, since I thought it was larger. My reasoning was to have a larger tank for that many more miles before refueling, a good way to save money on fuel by getting to the cheapest stations possible.
It had about 1/4 of a tank of highly questionable old fuel in it but I filled it up and ran it anyway. I figured the fresh fuel would dilute it enough. Thing is, I also replaced my fan clutch at the same time as I did the fuel line replacement. Immediately, my MPG was down a lot, which I thought might have been the fan clitch putting a heavier load. My coolant temp dropped by 10-15 degrees with the new fan clutch (and thermostat). I suspect the dirty old fuel in the tank, despite being mixed with 75% fresh fuel, still managed to clog the injectors. I was also running Howe's diesel cleaner (I forget the exact name) but it didn't seem to make an impact. Only 1oz per 10 gallons is what it calls for, but I often doubled it up to 4oz per tank for an an 18-19 gallon tank.
After a couple months of getting far worse MPG than I did earlier this year, I decided to buy a bottle of Hot Shots Diesel Extreme at Napa on sale. Reviews online praise it highly. There is only one old thread on here from 2017 and nothing much is even said about it, oddly enough. The ~$16 32oz bottle is 4 doses for my ~18 gallon tank. They say to dose it once every 6 months, so it's not too expensive. So I gave it a measured 8oz dose. Needless to say, my MPG has been restored to what it was. I was getting about 8 highway at best after switching to the rear tank, when I was getting 8.8-9.2 hwy this past summer on the front tank. I did notice my front tires were both 5PSI low so I topped them off a tank before I got the Hot Shot treatment, so I don't think it was exclusively that.
After the treatment, my mpg is way back up, 9.15mpg (90% highway). Not even joking.
It's not a miracle product if your fuel system is already as clean as it's going to get, but I'm sold on it working on a system that got highly questionable fuel run through it and had an immediate, noticeable drop. I know, one tank seems too soon to celebrate, but my fuel gauge is pretty darn accurate and it was right around the point it should be to accept ~12 gallons, and that's what it took on the fill-up.
Even if I account for a small margin of error and say it was actually 8.8mpg instead of 9.15, that's still in the ballpark of what I was getting before.
It had about 1/4 of a tank of highly questionable old fuel in it but I filled it up and ran it anyway. I figured the fresh fuel would dilute it enough. Thing is, I also replaced my fan clutch at the same time as I did the fuel line replacement. Immediately, my MPG was down a lot, which I thought might have been the fan clitch putting a heavier load. My coolant temp dropped by 10-15 degrees with the new fan clutch (and thermostat). I suspect the dirty old fuel in the tank, despite being mixed with 75% fresh fuel, still managed to clog the injectors. I was also running Howe's diesel cleaner (I forget the exact name) but it didn't seem to make an impact. Only 1oz per 10 gallons is what it calls for, but I often doubled it up to 4oz per tank for an an 18-19 gallon tank.
After a couple months of getting far worse MPG than I did earlier this year, I decided to buy a bottle of Hot Shots Diesel Extreme at Napa on sale. Reviews online praise it highly. There is only one old thread on here from 2017 and nothing much is even said about it, oddly enough. The ~$16 32oz bottle is 4 doses for my ~18 gallon tank. They say to dose it once every 6 months, so it's not too expensive. So I gave it a measured 8oz dose. Needless to say, my MPG has been restored to what it was. I was getting about 8 highway at best after switching to the rear tank, when I was getting 8.8-9.2 hwy this past summer on the front tank. I did notice my front tires were both 5PSI low so I topped them off a tank before I got the Hot Shot treatment, so I don't think it was exclusively that.
After the treatment, my mpg is way back up, 9.15mpg (90% highway). Not even joking.
It's not a miracle product if your fuel system is already as clean as it's going to get, but I'm sold on it working on a system that got highly questionable fuel run through it and had an immediate, noticeable drop. I know, one tank seems too soon to celebrate, but my fuel gauge is pretty darn accurate and it was right around the point it should be to accept ~12 gallons, and that's what it took on the fill-up.
Even if I account for a small margin of error and say it was actually 8.8mpg instead of 9.15, that's still in the ballpark of what I was getting before.
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