Jeep Renegade

[GKRenegade]

Hi, looking for suggestions on what to do to my 2015 jeep Renegade. It is the 2.4L, 9 speed auto FWD. looking at doing a belly pan, but not sure what else. Any ideas welcome!

[aardvarcus]

Some sort of gauge or instrumentation is a good start, I use an UltraGauge. It looks like the front spoiler is already in line with the lowest parts of the underbody, so a full air dam may not be needed, but you could always add larger tire spats in front of the wheels. If you go offroad at all use conveyor belt for durability.

Your biggest gains would be adding some sort of boat tailing, it looks like there is already some amount of taper built into the vehicle. Extending that taper would help, I always dreamed of building a 1-2 foot extension on the back of my wife’s 4Runner that would function as a boat tail disguised to look expedition-esque by incorporating a tire carrier and ladder.

When it is time for tires, that can make a huge impact. Pick a tire tread to match your usage, aka use street tires unless you need all terrains. Bigger diameter could help gearing, but with nine speeds and a 0.48 overdrive I doubt you need it so I would go back stock size.

There probably aren't any huge amounts of weight to be reduced, but try and keep from adding any additional weight that isn't needed.

[Fat Charlie]

If there's an "economy" button on the dash, press it and figure out how to work with it.

More speeds help "stab it and steer it" types save gas by keeping the engine in its happy place. Fewer gears help the efficiency minded save gas by staying in a higher gear instead of constantly hunting for the "right" gear. Chrysler's economy buttons generally keep the unit from downshifting as quickly and keep the torque converter locked up more, but that only helps if you meet it halfway.

And welcome!

[JRMichler]

The largest gas mileage improvement by far is from adjusting your driving habits based on feedback. The most important feedback is trip mileage for each trip. This typically is from a Scangauge or Ultragauge.

Observe how accelerating at different rates (stomp on it vs normal acceleration vs drive like a grandma) affects trip mileage. Observe the effect of headwinds, tailwinds, rain, snow, temperature, timing lights, timing stop signs, etc. Learn about and use DWB and DWL. Learn about the relationship between speed, gas mileage, and trip time.

How do you time a stop sign? By adjusting your speed (without using the brakes) so that you arrive just as the car in front is leaving. Then you only stop once and do not waste gas idling.

If that grille is as open as it looks, a grille block would be the next thing to try. But only after mastering the above.

[ThermionicScott]

Welcome to the forums, GKRenegade! Be sure to check out the "65+ ecomods" and "100+ hypermiling tips" articles at the top of the page.

[GKRenegade]

Seems as long as I keep it between 1500-2000 rpm it gets better mileage. I am toying with the idea of taking diamond plate for a full belly pan, and rear wheel covers. What is the concensus about taking the air box off and putting a cone filter in it's place? Or doing a drop in high flow with the intake snorkel off?

[aardvarcus]

Talking “special” air filters can bring out some strong opinions, but I will offer my suggestions. If you are talking about the oiled element cone/high flow filters, they are great for letting little particles into your engine. I prefer a real paper element filter, of which there are high flow versions if you are so inclined.

Since you have a gasoline engine, your biggest flow restriction in your intake system is the butterfly valve driven by your throttle, so to have a low restriction air intake system you will need to keep your throttle fully open at all times. In all seriousness, you would only see the gains from reduction in intake flow restrictions at or close to wot, as the actual job of the throttle is to throttle back (restrict) the amount of air going into the engine. Remember your car is constantly trying to maintain a certain air to fuel ratio.

With some vehicles, the MAF or other airflow sensors are relocated out of the factory parts into the aftermarket parts, which typically had larger diameters. This change caused the meaning of the readings the sensors were returning, and correspondingly caused the cars to run rich or lean. If it made your car run lean, you could actually see a slight bump in MPG, with the downsides associated with running a car engine lean.

Sucking air out of the engine bay versus the fender is a version of a “warm air intake” which could help mileage, by reducing the amount of oxygen in a given volume of air due to the increased temperature (remember fixed air to fuel ratio) but will hurt power.

[elhigh]

Diamond plate for your belly pan adds a fair amount of weight. Unless you're also a serious off roader - or even a sometime, casual off roader - then that's weight and strength you really don't need.

Don't do the air filter thing. Those make sense for racers who spend most of their time at high revs and need wide-open intakes with low restriction and have plenty of rebuild money, but that isn't where stock Jeeps live.

I am VERY curious to see how well this does as the Renegade, despite its Fiat genetics, is kind of appealing to me. Please make a garage page for your car so we can see what kind of results you get.

[vskid3]

The last study on this page found that dirty air filters don't hurt fuel economy on fuel injected cars compared to new air filters, just peak performance. I think it's safe to assume that a freer-flowing air filter won't help mileage either.

[GKRenegade]

Ok. Thank you for the suggestions. I think I will try to take the snorkel part off and see what that does first. Is it worth it to do a belles pan on the renegade? I don't do off roading. Just thought if I wanted to clean up the air flow and not worry about anything melting, that was a good way to go. Was going to put it on the wheel wells too for rear wheel skirts and front wheel gap filling.