Suburban Owners.. MPG?

[northfacetraveller]

Im lookin at a 1990 K2500 Suburban with a 5.7L and auto trans. Im curious what kind of fuel mileage you guys are getting. My plans for it are going to be for 6" lift, 38's and 4.88 gears..Outfitted for backroads travel.

What size is the tank roughly? and how many kms or miles do you usually get out of it? Please specify if miles or kms..

Thanks!!

 

[DT75FLH]

the sub i picked up...with 285/75/16 and 3.73 gears...running 75 mph gets me 9-10mpg (per gps)

5.7, 700r4 4x4 1/2 ton with 14bff rear 3"lift.

im going to 4.10 gears....it will down shift less out here as i drive some small hills back and forth to town. I've gotten as high as 13 leaving it in 3rd so I think it likes to be around 2500rpm on the highway. right now im about 2200 rpm at 75-77 mph

 

[WoldD90]

Mine get's 14-16 on the hwy, depending on terrain. 10-12 in the city and 8-12 towing. Stock tires, 6.0 and 4.10 gears.

 

[xpndbl3]

8 city and 11/12 highway mpg in a 88 suburban 3/4 ton on 35" tires and 6" lift kit

tank is either 31 gallons or 40 iirc in these models, so that should tell you the mileage possibilities.

 

[earthmuffin]

6" and 38's is gonna hurt....

I'm thinking you'll get 10 on a good day.

If better mileage is your goal you may want to consider the 6.2 diesel.
With sissy tires and 3.73's I can get over 20.

 

[Skratch]

My 90 w/ 454, turbo 400 and 3.73's gets 10mpg at highway no matter the speed.

My 87 w/ 350, 700R4, 4.10's 4" and 35's gets about 8mpg avg.

Both are full Silverados, 3 rows of seats, front and rear AC, cruise . . . both have 35 gallon tanks . . .
If you can squeeze close to 10 mpg out of it with 38's that's a small miracle and something to be grateful for. It's just the price we pay for having rigs with so much usable room.

As an aside, there is a 45 gallon tank available through some sources . . . no idea of the quality but I would be interested for back roads travel.
They had a couple tank options from the factory, 28, 32-35, and a 40 if I recall correctly, 32-35 being the most common.

 

[RADAR12]

Suburban

My 90 6.2 3.73 and 235/75/15 got 18.9 last time i checked commuting to work (combination of hwy speeds and city stop /go)

i have a 4.10 14 bolt waiting in the wings so with 33's it should do mid 20's on the highway. It doesn't help that our trucks are as areodynamic as a cereal box.

 

[turbohaulic]

We had a 96 burb that, on stock tire's, got 15-17ish. I don't know what size tank it had (I believe a 26 gal) but we could easily get 400 miles out of a tank. But with the lift, bigger tire's, and gear the mileage would be alot less. If your going to look for a new tank I'd get the biggest one you can fit/afford. You will never go wrong with to much fuel but running out is, well, not fun

 

[evldave]

Had an '88 Suburban. 350 w/Turbo 400 and 4.10 gears, 285-75-16 tires, and 40 gal tank. Drove it to Alaska and back (8,000 miles) got 12.1 mpg combined highway and off-road. In town, got around 12. Pulling my brothers 21' hunting boat, got 12 mpg. Sitting in the driveway, got 12 mpg. I think it might still be getting 12mpg I would fill up no later than 380 miles on the tank, just to be sure, but had to stretch a couple times and easily made it past 400 miles.

 

[redthies]

Wow... I must have been blissfully unaware in my 89 with 4" lift and 35s. I don't think I ever checked, but it always SEEMED better than 8-10mpg.

 

[northfacetraveller]

Thanks for all the replies!! Its kind of what I expected for the most part, as in "not good" but its the price to pay if you want all that space with a little power behind it. I figure its a pretty stout base for the things that I wanna do with it. I like the idea of building an elevated platform for sleeping, in the back while having storage underneath thus keeping things organized and minimalizing camp setup time, if always being on the move to a different location, but also being comfortable for long periods at a single camp.

 

[NapaBavarian]

Im lookin at a 1990 K2500 Suburban with a 5.7L and auto trans. Im curious what kind of fuel mileage you guys are getting. My plans for it are going to be for 6" lift, 38's and 4.88 gears..Outfitted for backroads travel.

What size is the tank roughly? and how many kms or miles do you usually get out of it? Please specify if miles or kms..

Thanks!!

My parents bought an '89 new in '88 and sold it last week, same as yours in every way, bone stock it got 10mpg its whole life, expect 6-8 with your lift and tires.

Standard tank was 30 gallons, optional was 40.

 

[jdinevens]

does anyone with a 6bt swap have any numbers for us? i'm curious as this is the route i'd like to take...

 

[coreys88burban]

does anyone with a 6bt swap have any numbers for us? i'm curious as this is the route i'd like to take...

X2 also LS (LQ4/9, LS1,2,....) swapped mpg please