Just picked up a 1986 isuzu trooper diesel(turbo). I have experienced an average of 23-24 mpg. Changed the oil, replaced the fuel filter, air filter etc, and still averaging about the same. I have heard that these beasts can reach 30 mpg but it seems unlikely having read previous posts. Just thought I would get the overal cencus of MPG on these guys.


Nick

I don't own a Trooper turbo diesel or have I continuously driven one to figure out the mileage. But according to fueleconomy.gov the 86 Trooper turbo diesel gets 28 mpg city and 28 mpg highway. In that case it gives you the fuel mileage of the vehicle when it is brand new and I think it would be pretty hard to try to push for 30 mpg in a used Trooper turbo diesel. But I believe if you can get great air flow to the turbo diesel and open up the exhaust with a 2.5" straight pipe system then you can gain 2-3 mpg from those mods.

I seem to average 24-25 around town(lots of idling, cold weather warm ups etc), but have gotten as high as 27 before on a trip that involved a lot of 55-60 mph on flat, country 2 lane. My mileage drops back off on 65 mph 4 lane interstate or hilly conditions.

BTW, I just installed a new K&N air filter and I think it is making a difference. My regular filter didn't really need changed (just 10,000 miles) and I have always had ambiguous feelings about K&N; but then had the chance to buy one cheap on Ebay[/url] so I decided to try it.

I have only driven 150 miles on it so it is hard to tell, but my fuel gauge is definitely already noticably higher than it would have been before the filter change(barely off full whereas before it would be almost down to 3/4 tank). Power may be better, at higher rpms, but I can't really notice it. But I swear it is making a difference in mileage.

BTW, my engine was recently rebuilt so this is new engine performance.

Good luck and I hope this helps,

NCDiesel

I know I can't compare to the boxy Trooper, but my Sonoma n/a got 42.7mpg (imperial gallons)the last tank. Most of my driving is around 50mph combines with town driving, but I also live in hilly terrain. Not much flat land where I live.
It definately drops when hauling the Kubota tractor behind. So does the speed. <img src="/forums/images/graemlins/cyclops.gif" alt="" />

Hi All--

Mine is not a Trooper either but it is hard to stay out of a mileage discussion. I have a 2 WD P'up with a turbo on a formerly n/a C223. I get about 39 to 40 miles per US gallon in mixed driving. About half is freeway driving at about 60 mph.
The truck has a camper shell on it and carries 3.42 rear end gears.

Paul <img src="/forums/images/graemlins/smile.gif" alt="" />

My 1982 Chevy LUV diesel that I have owned now for 4 years consistently gets 37 mpg. It is a longbed 2WD with the 5-speed transmission. The driving involves mostly town driving and on some occasions I drive over 55 mph. The fuel mileage I get is one reason why I love that truck. In the 4 years I have owned it I have never ran out of fuel and believe me I have gone past the E mark plenty of times. The thing is with these trucks is they are no horsepower machines and you have to look past that because they offer great reliability, great fuel mileage, one hell of a diesel engine, and simple, easy manufacturer designs.

I have 86 trooper diesel and get avg 23-25 mpg. Compared to the pups these trucks have much lower gearing therefore higher rpms at speed whichs cuts down the gas milage.

18-20 mpg

Jesse
278k

Mine would pull 21 in town and 25 on the highway. This was in Pueblo,CO (4700ft). I had put 31" tires just to get the rpms down enough to run 65@ 3000rpm. If you could keep the rpms around 2200-2500,it would do better.

NCdiesel, how is your fuel economy now that you have added the k and n filter? also, thanks for all of the responses.

Nick