1999 Chevy Suburban 99 suburban

1999 CHEVROLET SUBURBAN
25,000 MILES • V8 • 2WD • AUTOMATIC
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STEVE KYLLONEN
  • MEMBER
  • 7 POSTS
Im getting poor gas mileage after rebuilt motor installed.
Also pulled a 3000 lb. trailer 300miles and was struggling
Im getting 10 miles to a gal.or less now even after trailer

I should get 17 highway 14 city.
ive got new wires & plugs
Ive never changed fuel filte.

Note: before rebuilt motor install I got better mileage.
Mar 21, 2010 at 1:39 PM
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PEAR69
  • ✓ASE Certified Mechanic
  • 1,482 POSTS
  • ASE Certified Mechanic
When a motor is rebuilt properly, the cylinder bores are bored out a little larger. This will slightly increase the cubic inch displacement of the engine - which will consume moe fuel.
The 17 highway and 14 city mpg figures are probably not accurate....If these are factory figures, please consider that all factory mpg figures are done in a lab setting....
Mar 22, 2010 at 7:47 AM
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