8.1 2001 Suburban

[DOGMAN]

Still looking for a tow vehicle/family vehicle - found a 2001 8.1 Burban w/4.10 rear , leather , moonroof etc.... 23,000 miles on her- What kind of GAS mileage am I expecting with this combo? I never knew that the Subburban 2500 came with the 8.1. What are the problems with the earlier 01 8.1 engines?

[tbyrne]

12-13 MPG is common. Some people have complained about oil consumpsion problems but I haven't seen this in either of my trucks.

 

 

2002 8.1 Silverado HD - Full Throttle lift, 37" tires, Comp Cam, TOG headers, Volant induction plus more!

2002 8.1 Suburban -Intercooled Whipple supercharger, 22" wheels/tires + more - 407hp/558 ft-lb torque at the rear wheels - 13.93 @ 95.79 MPH

 

www.tbyrnemotorsports.com

[sxmax]

See my signature for my setup but I have exactly what you are looking at. Consistent 12-14 and have seen over 15 driving at 60 with the cruise set for long distances. The only time I have ever used any oil was pulling 6 sleds, 5 guys, & guy for 15 hrs straight each way through the mountains at 85mph . Used a half a quart each way, but I expected that with a big block. No other engine related problems other than small things like a thermostat & thermal fan clutch at 40k mikes. Would not trade the power for anything and I didn't buy it for gas mileage.

[Ben]

GM has "fixed" or "solved" the early big block oil consumption.

 

During the "discovery" process, they sealed some customers oil system. Sealed from the outside so that they could tell if the filler, dip stick, etc were messed with.

 

Turns out that wacky (very stupid) intake manifold bolting design and gasket at fault. Personally think bolting scheme main issue (not square to the sandwich of parts, those bolts, so sliding action to mess up the gasket).

 

Newer has better gasket design. Older has fix where they've gone away from OEM gasket and gone to FelPro. Mainly that O-Ring part of the OEM gasket does not like the sliding action of the new bolting scheme.

 

Visit buddies personal Suburban/Tahoe/GM Truck site. It's based on the Suburban forum. Here's link to both his site and the Sub forum:

 

#1 Son's place, Suburban/Tahoe/GM Truck info-help-HOW2 site

 

Suburban forum