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I recently had the Cruze recalled performed for the fire hazard due to oil on the engine under pan. On a 400 mile trip I experiened a reduction of about 4 MPG, not wanting to believe this I checked on my 400 mile return and saw about the same. Has anyone else noticed this? If I had know this I would have skipped the recall. I think an easier way to resolve the oil and fire hazard is to affix the under panel with hinges and when the oil needs to be changed the panel can be dropped down and cleaned and put back. I have tried to get the panel put back, however GM has modified the part and with a new part number. I inquired about getting the piece cut out of one of the Cruzes in for the recall and was told they could not do that. Does anyone know the original part number and if there is a place to get one. My only other choice is to try and find a Cruze in a salvage yard.
 

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I also noticed a big drop. I only had mine a week or so before having the recall done, so I didn't have accurate numbers, just the DIC. As I understand it, if you took care during the oil change, there would be no problem. I didn't know they were going to hack that big piece out. I intend to see if I can get a piece of aluminum and rivet it in place, to cover the huge piece they hacked out.
 

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I can see in some instances(high speed) getting less MPG with this shield modified for the recall, but there is no way its 4MPG less. The change your are indicating has to be some other factor.... fuel quality, tire pressure, temperature, AC use, & wind speed/direction all come to mind.

I have had the recall done for 2,000+ miles so far & if anything I have seen no significant change or even a slight increase in my MPG.
 

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I'm doubtful a 4 MPG drop could be attributed to this change (that's over 10%). There are so many variables to consider where fuel economy is concerned... wind speed, wind direction, elevation change, temperature, humidity, vehicle speed, other vehicles, tire pressures, gasoline ethanol content, air conditioning use, vehicle loading, and the list goes on and on. Without isolating these in a lab environment the only way for the common person to semi-accurately determine the impact of the change would be to do a series of back to back tests with the shield in place and without.

The shield is DEFINITELY responsible for lowering the car's drag coefficient, but I don't think it's enough to have anywhere near that kind of an impact on fuel economy.
 

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The shield is DEFINITELY responsible for lowering the car's drag coefficient, but I don't think it's enough to have anywhere near that kind of an impact on fuel economy.
...also, GM 'back-handedly' admits there is a FE penalty for the "chopped" under-panel in their response:

" Q12. GM has talked about the engine shield helps aerodynamics and improves fuel economy. How does the engine shield modification affect Cruze fuel economy?

A12. There is no impact on current EPA fuel economy estimates. For 2013, additional air pressure to the tires will offset any aerodynamic/fuel economy changes. "

...found in this GM document: http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM423104/RCORRD-12V288-6767.pdf
 

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I had my shield sliced & diced. No noticable change in MPG on the open highway. My ECO MT averaged (pump to pump) better than 45 MPG cruzing at 78 MPH.
 

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...also, GM 'back-handedly' admits there is a FE penalty for the "chopped" under-panel in their response:

" Q12. GM has talked about the engine shield helps aerodynamics and improves fuel economy. How does the engine shield modification affect Cruze fuel economy?

A12. There is no impact on current EPA fuel economy estimates. For 2013, additional air pressure to the tires will offset any aerodynamic/fuel economy changes. "

...found in this GM document: http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM423104/RCORRD-12V288-6767.pdf
Nice find!

The fact is YES, partial or full removal of this shield will negatively affect aerodynamics and therefore fuel economy. That is not in question. What is in question is the specific impact this modification will have. A 10% reduction in fuel economy is far from a reasonable estimate. I would be willing to bet the impact of this change would be less than the measurement error if real world (i.e. common man) testing were to take place.

On to your linked document, does anyone know what the tire pressure changes are for 2013? My 2012 Eco specifies 35/35 psi F/R.
 

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I recently had the Cruze recalled performed for the fire hazard due to oil on the engine under pan. On a 400 mile trip I experiened a reduction of about 4 MPG, not wanting to believe this I checked on my 400 mile return and saw about the same. Has anyone else noticed this? If I had know this I would have skipped the recall. I think an easier way to resolve the oil and fire hazard is to affix the under panel with hinges and when the oil needs to be changed the panel can be dropped down and cleaned and put back. I have tried to get the panel put back, however GM has modified the part and with a new part number. I inquired about getting the piece cut out of one of the Cruzes in for the recall and was told they could not do that. Does anyone know the original part number and if there is a place to get one. My only other choice is to try and find a Cruze in a salvage yard.
There is no way the shield recall is causing a 4 mpg drop mileage.


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I could see 1-2 mpg if they really hacked at it. 4 mpg is a bit hard to swallow.

There has to be another factor, such as more A/C use or a bad tank of gas.
 

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I could see 1-2 mpg if they really hacked at it. 4 mpg is a bit hard to swallow.

There has to be another factor, such as more A/C use or a bad tank of gas.
1-2 is still a lot. Maybe more like .5.


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My MPG has been slowly going up since I got my Cruze in Jan and even after the recall ticked up to 36.3mpg.
 

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LOL hack job. I signed the thing to refuse mine. I told them I need to see some more information first before they do mine.. they said "No problem, just be aware that when your engine catches fire it is not GM's fault" LOL assholes.
An easy reply would be, "with competent mechanics that shouldn't be an issue."

=P


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There is no way the shield recall is causing a 4 mpg drop mileage.


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It's not.. some are just too skeptical on the mod.

We were instructed to inform every customer coming in for the recall that a max of 1mpg can be seen lost. I actually followed up on many customers on their next return, 95% claimed no difference in mpg(a mix of city and highway drivers,both).

I haven't noticed a single thing, and up til now, completely forgot about hacking my own shield. I do plan on possessing a second full shield, to install over winter to keep the snow and salt off the engine and trans.
 

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I just picked up a 2013 Eco. Tire pressure is still 35psi
Welcome to CruzeTalk and thanks for the update. Boost your pressure to 40 for a slightly smoother ride and improved MPGs. Boosting above 40 and the suspension starts transmitting a lot more road bumps through to you. There are a few people who run their ECO tires at max sidewall.
 
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