# 2018 Cruze drastic decrease in fuel efficiency **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** chevrolet, cruze\ **Created:** [February 11, 2020, 4:49am UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309 "2020-02-11T04:49:17Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Wesley\_York](https://avatars.discourse-cdn.com/v4/letter/w/839c29/32.png) [@Wesley\_York](https://community.cartalk.com/u/Wesley_York)\ **Post date:** [February 11, 2020, 4:49am UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/1 "2020-02-11T04:49:17Z")
I purchased an aftermarket set of 18” wheels w/ new tires to replace the factory 16” wheels. Overall tire height and width are still the same but fuel economy decreased by an overall average of 10 mpg. It’s always averaged between 38-40 mpg. Now it averages 26-30 mpg. Even if the new wheels weigh a little more should it affect the fuel economy this much? Also, ever since I got the new wheels, the car shakes just a little bit when reaching speeds over 74 mph. It’s a very mild shake but can still feel it. The tire balance has been checked twice by two tire shops and they are perfectly balanced. ---
**Author:** ![Renegade](https://avatars.discourse-cdn.com/v4/letter/r/b4bc9f/32.png) [@Renegade](https://community.cartalk.com/u/Renegade)\ **Post date:** [February 11, 2020, 5:08am UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/2 "2020-02-11T05:08:10Z")
Now you know why it is not a good idea to change tire’s and wheel’s from factory spec’s. ---
**Author:** ![Wesley\_York](https://avatars.discourse-cdn.com/v4/letter/w/839c29/32.png) [@Wesley\_York](https://community.cartalk.com/u/Wesley_York)\ **Post date:** [February 11, 2020, 12:18pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/3 "2020-02-11T12:18:51Z")
some Cruze Premiers come with the same factory specs as the 18” wheels and tires that I purchased aftermarket so why would it be any different. mine is just an LT but same engine and everything. so doesn’t make any sense. ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [February 11, 2020, 12:21pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/4 "2020-02-11T12:21:49Z")
If they’re very heavy rims this might happen. ---
**Author:** ![Wesley\_York](https://avatars.discourse-cdn.com/v4/letter/w/839c29/32.png) [@Wesley\_York](https://community.cartalk.com/u/Wesley_York)\ **Post date:** [February 11, 2020, 12:25pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/5 "2020-02-11T12:25:10Z")
Not sure what they weigh since I never touched them. The weight may be the cause of the decrease in fuel economy. But still can’t figure out why the car still shakes slightly at higher speeds. ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [February 11, 2020, 12:26pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/6 "2020-02-11T12:26:45Z")
Could be a bad tire. What brand tires and wheels? ---
**Author:** ![CapriRacer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/capriracer/32/22_2.png) [@CapriRacer](https://community.cartalk.com/u/CapriRacer)\ **Post date:** [February 11, 2020, 1:57pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/7 "2020-02-11T13:57:34Z")
First, the OE tires (the tires that came on new vehicle from the factory) were designed with fuel economy at the forefront - and they get that by sacrificing treadwear and traction (especially wet traction). Most replacement tires are designed for either wear or grip and those will not have nearly the fuel efficiency of the OE tires. Second, new tires don’t give as good of fuel economy as worn tires - all other things being equal. So that’s a second hit in the FE department. You didn’t tell us what the UTQG rating was of both tires, but I’ll bet you went towards better wear, so you took a third hit. You also didn’t tell us what tire sizes you went from or to, and that can have an effect as well. Yup, you should be seeing a loss of fuel economy, and depending on what you did exactly, the loss could be quite large. ---
**Author:** ![shanonia](https://avatars.discourse-cdn.com/v4/letter/s/9de053/32.png) [@shanonia](https://community.cartalk.com/u/shanonia)\ **Post date:** [February 11, 2020, 4:18pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/8 "2020-02-11T16:18:22Z")
The effects of wheel/tire weight on HP at the wheels. Fuel economy would also be reduced, although this article does not address that. To get the familiar amount of acceleration you’d have to have the gas pedal pressed down more now. Not good for MPG! [https://books.google.com/books?id=Y7P6BFss\_0cC&pg=PA24&lpg=PA24&dq=understanding+wheel+weight&source=bl&ots=vC2UL47Mq-&sig=FX4EEXhGP\_htzZLe2tNGrGVFYFA&hl=en&sa=X&ved=0CFcQ6AEwCWoVChMI-K6Kr6DsxgIVTTKICh3SLg0z#v=onepage&q=understanding%20wheel%20weight&f=false](https://books.google.com/books?id=Y7P6BFss_0cC&pg=PA24&lpg=PA24&dq=understanding+wheel+weight&source=bl&ots=vC2UL47Mq-&sig=FX4EEXhGP_htzZLe2tNGrGVFYFA&hl=en&sa=X&ved=0CFcQ6AEwCWoVChMI-K6Kr6DsxgIVTTKICh3SLg0z#v=onepage&q=understanding%20wheel%20weight&f=false) ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [February 11, 2020, 4:22pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/9 "2020-02-11T16:22:03Z")
Car and Driver found about a 10% hit to mpgs when testing high quality tires and wheels. We don’t know what the new tires and wheels are in this case: > **[Effects of Upsized Wheels and Tires Tested](https://www.caranddriver.com/features/a15130598/upsized-wheels-tires/)** > > Plus-Size Models: Testing the performance effects of upsizing wheels and tires. ---
**Author:** ![Wesley\_York](https://avatars.discourse-cdn.com/v4/letter/w/839c29/32.png) [@Wesley\_York](https://community.cartalk.com/u/Wesley_York)\ **Post date:** [February 11, 2020, 7:51pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/10 "2020-02-11T19:51:08Z")
Factory tires were Hankook Kinergy GT 205/55R16. New tires are Cosmo MuchoMacho 225/40ZR18. ESR SR12 wheels I did expect maybe a slight decrease in FE but not this much for both city and highway driving. Even at lower city driving speeds it’s only averaging 25 or so when it used to be 35 ---
**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\ **Post date:** [February 11, 2020, 7:57pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/11 "2020-02-11T19:57:29Z")
There is no way I would tell anyone I put ’ MuchoMacho ’ tires on my vehicle . I did a little online research and there is no reason to purchase these ultra cheap tires except for a junk vehicle you want to get rid of. I would not trust these things at turnpike speeds at all. ---
**Author:** ![PvtPublic](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/pvtpublic/32/13089_2.png) [@PvtPublic](https://community.cartalk.com/u/PvtPublic)\ **Post date:** [February 11, 2020, 8:00pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/12 "2020-02-11T20:00:34Z")
> [@Wesley\_York](#): > > New tires are Cosmo MuchoMacho 225/40ZR18. I think its because of the garbage tires. Just my opinion. ---
**Author:** ![circuitsmith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/circuitsmith/32/40376_2.png) [@circuitsmith](https://community.cartalk.com/u/circuitsmith)\ **Post date:** [February 11, 2020, 8:04pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/13 "2020-02-11T20:04:15Z")
If those aftermarket wheels don’t have the right amount of offset they can add a tilt to the hubs, changing wheel alignment and adding stress to the wheel bearings. Modding a car is like playing table games in a casino: best to not play the game if you don’t understand the rules! ---
**Author:** ![Wesley\_York](https://avatars.discourse-cdn.com/v4/letter/w/839c29/32.png) [@Wesley\_York](https://community.cartalk.com/u/Wesley_York)\ **Post date:** [February 11, 2020, 8:11pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/14 "2020-02-11T20:11:00Z")
I read up on it before hand and hadn’t read about anyone having any problems with aftermarket wheels on this car. And I made sure to keep the tire size, wheel size and offset the same as the 18” factory wheels that come on the premier trim models. And yes I should’ve researched the tires more I admit that. I just asked the tire guy to order me some tires that weren’t cheap but I didn’t want anything super expensive either. Told him to get something in between and he told me these were good tires. Charged me $150 each for them. If these tires are really that crappy maybe I should give him a call… ---
**Author:** ![ledhed75](https://avatars.discourse-cdn.com/v4/letter/l/f6c823/32.png) [@ledhed75](https://community.cartalk.com/u/ledhed75)\ **Post date:** [February 11, 2020, 8:31pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/15 "2020-02-11T20:31:54Z")
Is it too late for you to return the wheels and/or get your old wheels back? Being a 2018 car, I’d wonder if this is still in the factory warranty period.If you have any sort of suspension or related issues, the dealer might could blame the non-OEM wheels. Even if you have to eat the cost of the 18" tires, you might be better off. Just a thought. ---
**Author:** ![Wesley\_York](https://avatars.discourse-cdn.com/v4/letter/w/839c29/32.png) [@Wesley\_York](https://community.cartalk.com/u/Wesley_York)\ **Post date:** [February 11, 2020, 8:39pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/16 "2020-02-11T20:39:48Z")
Yes it’s still under warranty and I still have the stock wheels and tires. I kept them just in case I had any issues I could throw on the factory wheels so warranty won’t be voided ---
**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\ **Post date:** [February 11, 2020, 8:50pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/17 "2020-02-11T20:50:07Z")
@CapriRacer Do you want to make a statement about these Cosmo tires as you are the tire expert ? ---
**Author:** ![shadowfax](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/shadowfax/32/13026_2.png) [@shadowfax](https://community.cartalk.com/u/shadowfax)\ **Post date:** [February 11, 2020, 9:04pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/18 "2020-02-11T21:04:38Z")
> [@Wesley\_York](#): > > same factory specs as the 18” wheels and tires that I purchased aftermarket Yeah, but they aren’t the same wheels. If yours are heavier, and/or have more of the weight toward the rim rather than the hub, then you’re making your car work a lot harder to spin them. And btw, the Cosmo tires weigh 6 pounds more than the Hankooks did, so that’s 24 more pounds, all the way on the outside of the wheel which is the worst possible place to add weight, that your car is having to fight. As to why it shakes slightly, either a bad tire like @texases said, or bad balancing. Low-profile tires often require roadforce balancing in order to get the balance right. A normal balancer won’t do. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/48514_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [February 11, 2020, 9:33pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/19 "2020-02-11T21:33:20Z")
> [@VOLVO\_V70](#): > > There is no way I would tell anyone I put ’ MuchoMacho ’ tires on my vehicle . +1 Those are truly GARBAGE tires. Take a look at this: > **[You May Want to Skip These Cheap 'Sexy Beast' and 'MuchoMacho' All-Season Tires](https://www.thedrive.com/news/30911/you-should-probably-skip-these-cheap-sexy-beast-and-muchomacho-all-season-tires)** > > Funny names. Unfunny decision. 👍 ---
**Author:** ![shadowfax](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/shadowfax/32/13026_2.png) [@shadowfax](https://community.cartalk.com/u/shadowfax)\ **Post date:** [February 11, 2020, 11:27pm UTC](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309/20 "2020-02-11T23:27:42Z")
Well, I agree that they’re most likely garbage based on the price and the fact that they seem to be putting a lot more thought into marketing and appealing to teenagers than into things like, you know, tread and construction. But that article is pretty stupid. “I don’t know anything about these tires and I haven’t actually tested them but I’m purdy sure they’re gonna suck because they have stupid names and don’t cost much” is the essence of what he’s saying. [Next page](https://community.cartalk.com/t/2018-cruze-drastic-decrease-in-fuel-efficiency/158309.md?page=2)