On a different thread, someone was talking about an ops mod and claimed 3-4 mpg gain. Could someone tell me what this is? And better yet how to do it and how hard it is? Plus the materials I'll need to do it as well.

Thanks

 

Google "OPS relay mod" although it does not apply to your truck,it is still info you can use to help others.

 

So is it only useful for pre-OBDII 6.5s?
Darn

 

Yes they depend solely on the OPS for LP power when the engine is running-the relay still uses the OPS for a signal but carries all the current for the LP taking the strain off the OPS.

The person who got better mileage would have done so only because his LP was once again working and he would not have had his foot buried in the throttle all the time to find any power-these trucks feel like 4 cylinders when the LP quits pumping fuel.