How can I increase my 2002 Tahoe 4WD LT's Fuel Economy???

[drakon543]

 

[06_2WD_Z71]

To find out what gear ratio your truck came with, check the RPO sticker in the glovebox and look for the following codes:

GT4 Rear axle, 3.73 ratio
GT5 Rear axle, 4.10 ratio
GU5 Rear axle, 3.23 ratio
GU6 Rear axle, 3.42 ratio

If you don't have enough gear, one thing you'll notice is the transmission dropping out of OD on the highway on any sort or grade or headwind. When that happens the back and forth is hurting your mileage.

My truck came with the horrible 3.23 gear. With stock tires it was bad. On our family vacation loaded down with gear it was dropping out of OD all the time. With 34" tires it was even worse. It was a pig and always seemed to be struggling in the wrong gear. I put in 4.10s, and the truck now does everything effortlessly without messing with the gear lever. I might should have gone with 4.30s, but so far 4.10s seem just about right for me.

If you have 4.10s or even 3.73s, it might not be worth the money to swap if the truck seems like it is running ok.

 

[xFuZzYx]

To find out what gear ratio your truck came with, check the RPO sticker in the glovebox and look for the following codes:

GT4 Rear axle, 3.73 ratio
GT5 Rear axle, 4.10 ratio
GU5 Rear axle, 3.23 ratio
GU6 Rear axle, 3.42 ratio

If you don't have enough gear, one thing you'll notice is the transmission dropping out of OD on the highway on any sort or grade or headwind. When that happens the back and forth is hurting your mileage.

My truck came with the horrible 3.23 gear. With stock tires it was bad. On our family vacation loaded down with gear it was dropping out of OD all the time. With 34" tires it was even worse. It was a pig and always seemed to be struggling in the wrong gear. I put in 4.10s, and the truck now does everything effortlessly without messing with the gear lever. I might should have gone with 4.30s, but so far 4.10s seem just about right for me.

If you have 4.10s or even 3.73s, it might not be worth the money to swap if the truck seems like it is running ok.

I saw the GT4 on that sticker, so that means that I have 3.73 gears, right? Sense im running 35x12.50's on 20x14's (an extremely heavy tire combo, each of my wheels weigh more than my friends 38x13.50's on his factory 17" wheels) and I always have at least 600+ lbs of audio gear in my truck that stays in there plus whatever else I pack for my trips, what do you think would be the best gear ratio for me to get the best gas mileage that I can while still maintaining some power?

 

[TheAutumnWind]

You aren't going to get much better mileage than that. Gears, fans, and tune, plus basic maintenance stuff will help though.

My slightly lowered stock denali on stock wheels averages like 13mpg...

 

[xFuZzYx]

You aren't going to get much better mileage than that. Gears, fans, and tune, plus basic maintenance stuff will help though.

My slightly lowered stock denali on stock wheels averages like 13mpg...

At this point any increase is worth it. I usually try to go on like 1 road trip a month and some of these trips are 1 day trips where I'll drive anywhere from 100 to 500 miles in 1 day. And if I go on a full weekend trip I'll drive anywhere from 300 to 1600 miles in like 3 days. So whenever I'm taking these longer drives, if I can save a good bit of money on gas then it's completely worth any increase to me.

 

[massivespl]

In my 2002 Tahoe,When I went to slamology this year towing a 4000lb+ Chevy HHR and my truck with 4 alternators and 26" rims I was getting 12mpg on they way there and about 15mpg on the way back because it was more down hill on the way back. I was very pleased with the MPG while towing. I just have cheap eBay cold air intake with an as seen on TV tornado in the intake lmao

 

[Red Rider]

i did some reading when i first got my stock truck. But people always post mods claiming amazing advantages, but never back it up with proof. It would be nice to do a test with each mod. and do dyno test before and after.

 

[TheAutumnWind]

i did some reading when i first got my stock truck. But people always post mods claiming amazing advantages, but never back it up with proof. It would be nice to do a test with each mod. and do dyno test before and after.

It would be nice. dyno runs aren't free though.

That being said there is tons of dyno proven mods for the LS engines.

 

[TheAutumnWind]

At this point any increase is worth it. I usually try to go on like 1 road trip a month and some of these trips are 1 day trips where I'll drive anywhere from 100 to 500 miles in 1 day. And if I go on a full weekend trip I'll drive anywhere from 300 to 1600 miles in like 3 days. So whenever I'm taking these longer drives, if I can save a good bit of money on gas then it's completely worth any increase to me.

long tubes might be worth considering.

 

[08HoeCD]

Suggest that you look at all options, and their costs, then determine how much fuel-cost you can truly expect to save per option, then choose accordingly.

Sounds simple, but many of us will find that the cost of the fuel-saving option exceeds the actual cost of fuel saved.