Gas Mileage

[geezer101]

You can get an improvement on power if you tune the engine to run on the stuff. You will also need to add an upper cylinder lubricant feed to the intake to prevent the issues of valve wear. The upside is LPG is cheaper than regular fuel but the downsides are the amount of space the LPG tanks take up and the extra fuel consumption. You will find that engine oil looks cleaner for longer when using LPG and the combustion chambers don't carbon up (but don't be a monkey and think you can get away with doing extended duration oil changes) - and if you run into issues you will need to take it to an experienced LPG technician. And yes, trying to start an engine running on LPG when it's really cold is a biatch. Messing with LPG is not an option for the DIY mechanic as a system leak could turn your truck into a rolling inferno...

[Brady H]

My 89' 4x4 standard cab mighty max gets about 19 around town and about 24-25 on the high way cruising in 5th gear usually. Its a 2.6 with the weber carb kit. And it seems to be very constant as far as I have monitored.