Last post on Jun 25, 2013 at 11:15 AM
You are in the Chevrolet Suburban & Tahoe
What is this discussion about?
Chevrolet Suburban, Chevrolet Tahoe Limited/Z71, Chevrolet Tahoe, Fuel Efficiency (MPG), SUV
#2 of 186 interesting, the huge yawn this topic gets
Sep 15, 2005 (6:46 pm)
I've driven a slew of new cars and trucks, and I'm a little OC about checking my milage, miles/fuel purchased. I never believe the trip computer. I consistently get 15+ around town in my 04 Tahoe (5.3V8, 2wd, standard axle) and 18-19-20 hwy depending on speed and road conditions. While those numbers may not qualify as an econo-car, they also do not justify the "gas guzzling" image big GM SUV's have. My x-01-Toyota Sienna promised very high numbers on the window sticker but never did better than high 16's in town and 20/21 hwy. My wife's 04 Lexus RX330 gets high 17's city (no experience on the highway) but that is offset using premium fuel. Dollar for dollar, it costs about the same to run her RX a thousand miles a month as my Chevy. The best kept secret in the auto industry is that GM makes big trucks that get pretty darn good milage. Go figure.
#3 of 186 2003 5.3V8, 4wd MPG
Sep 16, 2005 (4:45 am)
We also get about 15 mpg in town (slightly less in the winter) and about 18 to 20 on the highway. We have gotten as high as 23 (three tanks in a row) in certain conditions but 19 is the average mpg on the highway. When we tow the camper and have 4 bikes on top the MPG drops to 16ish on the highway.
#4 of 186 Different axle gear ratios - better mileage?
Sep 16, 2005 (12:48 pm)
Hi all - we are considering purchase of '02-'04 4x4 Suburban and have concerns re: mileage. Salesman last night mentioned different rear axle gear ratios and said that there were 2 different options. He said that they would have similar performance on highway but that one was definitely better for in-town. I saw mention of "standard axle" in dardson1's entry (#2 in this thread) so I thought maybe someone here could explain options and benefits of each and give a little insight to a Suburban "newbie". THANKS!!
#5 of 186 Re: Different axle gear ratios - better mileage? [davew3]
Sep 16, 2005 (2:26 pm)
as I understand (even though I do not tow), you need a higher number axle ratio if you plan to do serious towing. A lower number will increase economy in normal driving. I had an 02 Tahoe (3.73 axle) and now have an 04 (3.23 axle). Both had the 5.3 engine and 2wd. I get about a mile per gallon better, city. Of course, that assumes they didn't make other modifications to squeeze a few more drops of gas out of the trucks between 02 and 04. good luck
#6 of 186 Re: Different axle gear ratios - better mileage? [dardson1]
Sep 16, 2005 (11:33 pm)
Thanks for info...of course, now I'm even more confused than before as the salesman was telling me that the higher ratio gears will get better in-town mileage...upwards of 3-4 mpg improvement. His reasoning was that the lower ratio gears cause the tranny to downshift more often when going up slight inclines and that the downshifting then causes the engine to work a little harder and hence the gas mileage goes down. What kind of mpg numbers are you getting with your '04? Any others out there care to share numbers too? Thanks!!
#7 of 186 Aftermarket Overdrive Units... any experience?
Sep 22, 2005 (5:30 pm)
Looking for someone who's purchased an aftermarket overdrive for their Suburban or Tahoe. I'm looking at a GearVendor unit that promises a 20% improvement in MPG. Based on the MPG saving and my annual miles plus $3 a gallon gas, the unit should pay for itself in 6 years. I have a 3/4 ton 4wd with a 6.0L and 4.10 differential ratios. Current MPG is 13.0 for a 80% city 20% highway mix or 14.8 to 16.0 MPG straight highway depending on driving speed (really drops off above 65 MPH).
#8 of 186 Re: Different axle gear ratios - better mileage? [davew3]
Oct 31, 2005 (11:50 am)
Gotta be careful when saying higher and lower ratio, because the effect is reverse of the terminology.
In general, if you have a lower ratio rear end (3.73 or 4.10), you will have better acceleration, a higher tow rating, and possibly lower fuel mileage. A higher ratio (e.g., 3.23) gives, in general, slower acceleration, lower tow rating, and higher 'highway' mileage. And most likely, downshifts won't occur as often with the 3.73 or 4.10.
Now, if that makes things straightforward, let me throw mud on it. GM makes a 4.8 and a 5.3 V-8 for the Tahoe (or used to). Most people who have bought the 4.8 did so for gas mileage, yet most people who have the 5.3 get better mileage. Real world says that people develop an expectation of performance and mash the gas pedal until they get it. So as a result, most people work the 4.8 to death and pay for it at the pump.
I suspect that if you coupled a 4.8 with a 4.10 or 3.73 and matched it with a 5.3 with a 3.23, the gas mileage and performance would be comparable. I tow with a 5.3 and a 3.73, but if I move to the fifth wheel, I would go for the 5.3 and a 4.10 because it would get better gas mileage and provide better performance (engine wouldn't be working as hard).
Additionally, most engines have a sweet spot for fuel economy. My Tahoe gets worse mileage at 55 towing (about 15), then it does at 60 or 65 (about 16-16.5). On the highway, no trailer, at 65 mph, I get over 20 mpg, but I can get 13 with a lot of in town driving.
#9 of 186 lately bought an 06
Nov 14, 2005 (7:07 pm)
Had an 02 with 5.3 2wd and 3.73 axle and it got mid to high 14's. Had an 04 5.3 2wd w/3.23 axle and got low to mid 15's. New 06 5.3 2wd w/3.23 axle first three tanks is getting close to 16. This is all mostly city with 15-20% freeway. I drive fairly conservatively. I could likely lower those numbers 2mpg by driving it hard. Can hardly believe they can squeaze this kinda milage from a beefy V8. love my Tahoes
#10 of 186 '04 2wd with K&N/Flowmaster
Dec 17, 2005 (8:05 am)
After we bought our Tahoe, we were driving twice a week to Jacksonville, FL. I put a K&N FIPK and a Flowmaster 40 series on it. The gas mileage improved by an obvious amount. We ended up with about 1/8 a tank more fuel in the tank after the mods than before. The numbers by the tank full hover around 23mpg for us. This is considering that I have a lead foot and thouroughly enjoy the sound of the exhaust. Consider that my '98 Gr Cherokee with 4.56 gears and 33" tires on a 4.0 6cyl gets about 15mpg.