Same sub-par mileage even after IP re-timed.. ugh!

[ghunt]

Synthetic oils in the complete drivetrain have been tested by the Federal GOV to increase miles per gallon by 8% when properly installed.

I get 20+ mpg in my dually, That I am happy to own.

Javier

It's not recommended to switch to synthetics on an engine that already has significant mileage because you are more likely to develop oil leaks in various places. Dino oil eventually builds up deposits in some areas, and when you switch to synthetic it will erode these deposits and often lead to leaks around old gaskets.

 

[jam sandwich]

Well I took some brake cleaner around and below the IP and cleaned some things up and noticed a 'STANADYNE REMANAFACTURED' tag on the side of the IP.. so this means it's not the stock IP.. but who knows how many miles are on it..

 

[dsltech83]

15 MPG is about what I get with my truck, I know the injectors need replaced, had one out when I changed my glow plugs a couple weeks ago, pop tested it and was a pretty good dribbler so I know i'm loosing some mileage there.

 

[Sycostang67]

My 86 gets 16-18 with 189k on stock IP/Injectors and I haven't even tried driving gently. I'm not flogging it, but I'm not exactly driving to achieve maximum mpg. My 93 can get 18 but usually gets 14 due to me loving the sound of the turbo too much.

 

[Popeye2347]

Where is your water temp needle? For best fuel mileage it should be, IIRC about 1/3 into the normal range when up to operating temp.[read the FAQ'S] ---seems to me like 190F at the top hose if you have an infrared thermometer. Replacing the thermostat with an oem Ford one increased my mileage 3-4 mpg.