I have a 95 RRC LWB with a 3" RTE lift and 255/85/55 BF Mudd Terrains and I am getting 10mpg. I wasn't expecting too much better, but is this normal and what are somethings I can do increase it? As of right now the top is bare so no rack or anything.

 

You can remove the lift and put on less aggressive tires.
The more wind resistance the lower the MPG, so raise the truck and expose the axles and you reduce MPG.
Aggressive tread also increases rolling resistance which reduces MPG.

 

It would take WAY too long to recoup the costs of lowering the truck. I'm not expecting to get amazing MPG, but I know people with similar lifts, larger tires and racks getting 4 mpg better than me.

 

How tall are those tires? The "55" does not make sense. The tire size will impact more than the lift itself.

 

Is everything else OK on the truck? As an example, if your thermostat is stuck open, you won't overheat, but MPG will suffer. Same for some sensors.

 

Some people I've learned on these forums really suck at math. They might not be taking into account odometer error from the tires etc. Also the terrain traveled will have an effect as well.

 

Are you aware that when your Range Rover was brand new, traveling on skinny 205/85/16 tires, the EPA estimate for around town driving was estimated at 12 mpg. Now, 17 years later with significantly larger tires you're surprised with 10mpg?

I owned one of these LWB's back then when it was brand new. I seldom got better than the EPA estimates for around town and highway driving. They were pigs then and they're even worse today.