# 2007 Chevrolet TrailBlazer- Mileage drop **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** chevrolet\ **Created:** [November 11, 2019, 3:59pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574 "2019-11-11T15:59:50Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![paulyahnke](https://avatars.discourse-cdn.com/v4/letter/p/b38774/32.png) [@paulyahnke](https://community.cartalk.com/u/paulyahnke)\ **Post date:** [November 11, 2019, 3:59pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/1 "2019-11-11T15:59:51Z")
My gas mileage has dropped by 2 mpg. Usually get 16 now is 14. Any suggestions from other owners on how to improve would be appreciated. It has about 122k for mileage ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [November 11, 2019, 10:20pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/2 "2019-11-11T22:20:54Z")
I would suggest you need a new thermostat. It is open a bit and not warming up the truck quickly enough. That is, unless you just got a new set of tires and noticed this drop. Then the mileage drop is likely a fault of the tires. ---
**Author:** ![It\_s-Me](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/it_s-me/32/12660_2.png) [@It\_s-Me](https://community.cartalk.com/u/It_s-Me)\ **Post date:** [November 11, 2019, 10:36pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/3 "2019-11-11T22:36:30Z")
If you are just doing short trips, and with it being colder out, your engine isn’t running long enough to get up to operating temperature. ---
**Author:** ![paulyahnke](https://avatars.discourse-cdn.com/v4/letter/p/b38774/32.png) [@paulyahnke](https://community.cartalk.com/u/paulyahnke)\ **Post date:** [November 12, 2019, 10:47pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/4 "2019-11-12T22:47:15Z")
y’know, it just cold here and i noticed the heater doesnt seem to be as warm which would indicate a thermostat problem too right. Is it difficult to replace? ---
**Author:** ![paulyahnke](https://avatars.discourse-cdn.com/v4/letter/p/b38774/32.png) [@paulyahnke](https://community.cartalk.com/u/paulyahnke)\ **Post date:** [November 12, 2019, 10:47pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/5 "2019-11-12T22:47:49Z")
BTW no new tires ---
**Author:** ![kurtwm1](https://avatars.discourse-cdn.com/v4/letter/k/13edae/32.png) [@kurtwm1](https://community.cartalk.com/u/kurtwm1)\ **Post date:** [November 13, 2019, 12:05am UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/6 "2019-11-13T00:05:48Z")
Not really… ---
**Author:** ![vipergg](https://avatars.discourse-cdn.com/v4/letter/v/50afbb/32.png) [@vipergg](https://community.cartalk.com/u/vipergg)\ **Post date:** [November 13, 2019, 1:37am UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/7 "2019-11-13T01:37:43Z")
Either thermostat is opening too quick or it is simply the switch to winter blend gas which lowers your mileage . If the stat is bad though usually you will get a CEL with a P0128 code set . ---
**Author:** ![It\_s-Me](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/it_s-me/32/12660_2.png) [@It\_s-Me](https://community.cartalk.com/u/It_s-Me)\ **Post date:** [November 13, 2019, 2:16am UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/8 "2019-11-13T02:16:43Z")
> [@vipergg](#): > > simply the switch to winter blend gas which lowers your mileage Depending on where you live, ours is 10% ethanol year round. ---
**Author:** ![paulyahnke](https://avatars.discourse-cdn.com/v4/letter/p/b38774/32.png) [@paulyahnke](https://community.cartalk.com/u/paulyahnke)\ **Post date:** [November 13, 2019, 3:33am UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/9 "2019-11-13T03:33:32Z")
Thanks much! ---
**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\ **Post date:** [November 13, 2019, 8:13pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/10 "2019-11-13T20:13:16Z")
My trailblazer set a CEL for running too cool indicating I needed to replace the thermostat, I would find if your car is the same before worrying about the thermostat. I lost 2 mpg after new tires probably 8 years ago and never got it back. Asked a mechanic bud to check, he found nothing except a leaking fuel pressure regulator, and it did not help gas mileage. New plugs and filters did not help either. I’ve thought about doing an o2 sensor just for kicks, but have not gotten around to it. ---
**Author:** ![paulyahnke](https://avatars.discourse-cdn.com/v4/letter/p/b38774/32.png) [@paulyahnke](https://community.cartalk.com/u/paulyahnke)\ **Post date:** [November 14, 2019, 4:41pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/11 "2019-11-14T16:41:15Z")
Thanks for your input ---
**Author:** ![pyrolord314](https://avatars.discourse-cdn.com/v4/letter/p/6a8cbe/32.png) [@pyrolord314](https://community.cartalk.com/u/pyrolord314)\ **Post date:** [November 14, 2019, 5:18pm UTC](https://community.cartalk.com/t/2007-chevrolet-trailblazer-mileage-drop/152574/12 "2019-11-14T17:18:33Z")
> [@It\_s\_Me](#): > > Depending on where you live, ours is 10% ethanol year round. Winter blend vs summer blend has nothing to do with Ethanol concentration