14-17.5mpg w/90,000 miles on it and a fresh tune up
no
SLX is a step up form the SLE
how many km's on the engine? It could just be tired and worn out, a tune-up won't fix that.
there is a diagram on the either on the left side of hood latch,or up on the hood its self
There is a place on 95 GMC sierra 4wd pick up that has the trim name and actually it is referred to as Sierra Trim.
Could be in need of a tune up.
Ext cab 99 GMC sierra gross weight 6400lbs
Sierra 1500: up to 10,700 pounds Sierra Hybrid: up to 6,100 pounds Sierra Denali: up to 9,600 pounds
The cabin air filters are located in the heater box above the lower panel, mounted below the glove box.drop the plastic panel, 3-7mm screws, then you will see a black access panel, with 1 screw holding it up. the 2 filters are located there. Sorry, I misread the question and read it as 2000 GMC Sierra. Your 2008 GMC Sierra doe not have a cabin filter.
check up front in the condenser
in the radiator reservoir