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Paralize
11-05-12, 11:12 PM
Just wanta know what fuel consumption I can expect from my JK 2012, 3.6l auto..

Bear suggested to lower my tyre pressure (next test on fill up)..

I mean really I thought I was getting a sports car... 60ltr tank.

Seems that I am going through a lot of fuel and I am not really doing anything out of the ordinary cuz I aint got no bull bar. (When I get this I can bulldoze through anything)..

yikes so far 14ltrs/100km...

It's not about the cost of the fuel, its about running out of fuel.....

At the end of the day, its totally cool to have a "sports car" that knows what real sports are.... So sorry Mercede's that you compressed your Kompresser into a really expensive boat anchor...

"She bought a Jeep!"..........

Don't hold back!

Linda

Bear
12-05-12, 12:12 AM
Don't expect fantastic fuel figures yet, your motor is not run in yet.

Regarding tyre pressure I suggested you run at 38--40 psi on the road, and lower the pressure to 20 psi off road.

My 2door rubicon gives me 11.8lt/100km. I put the back seat back in the vehicle for the school holidays and the figure went up to 12.5. With 4 people in the car the figure went up to 13.2.


Bear

Paul-JK
12-05-12, 08:57 AM
Hi Linda,

Firstly, love your posts so keep them up. Always bring a smile to my face.

Yeah, fuel consumption and Wranglers :hororr:. The JK's aren't actually that bad when compared to the TJ's or even to other 4WD's but I would safely say you can ignore the sticker it had on the windscreen when you got it. Mine's a 4dr CRD so my figures aren't much use to you but you will need to give the engine time to run in a bit and for you to get used to the car before the fuel consumption will drop. Mine was terrible for the first 5000km and then steadily dropped until I had about 20000km on it. It's still not as good as others say they get but it's not too bad either. Around town (where it spends far too much of it's time) they like a drink as they have a lot of dead weight to keep stopping and starting and on the freeway the aerodynamics (or lack thereof) really don't help. A decent headwind can easily add 1 or 2l/100km. I would say if you're getting 14l/100km when it's brand new then that's not too bad and it will drop over the next few months. Are looking at the figures on the dash or calculating them yourself? I've found the figures on the dash are OK as a general guide but are not often that accurate.

As for tyre pressures, bit of personal preference really. I ran mine stock tyres at 34psi (cold) on the road. Running them higher than that might have helped the fuel consumption more but the ride on the stock suspension was harsh enough already (especially when the car was empty) and with the tyres at 40psi I though it felt like I was going to shake the car (and me) apart. Dropping them a little took a little bit of the bite out of it. Off road I used to drop to 28psi (hot) for normal trails (which really helps smooth out the ride) and anywhere as low as 20psi if it gets really rough or wet. Just a case of playing with them to see what you prefer.

Dieselcon
12-05-12, 07:43 PM
Not sure if it applies to the 3.6 penstar engine but have been told to the run in period should be done at variable load and rpm. Ie don't cruise on the highway for long periods at constant rate. Give a few thousand km and your economy should improve. Is your an auto?

TRBN8R
13-05-12, 08:57 AM
I have a 4dr 3.8 auto.... I started off when it was brand new at 18-20 ltrs/100.... from there it gradually got better..... Engine will suddenly stretch its legs when u hit 5000k mark..... I am running a 2.5 inch lift, 33inch muddies, Bull Bar and a snorkel and I am getting about 15Ltr/100 in city driving from Blacktown to Silverwater in peak traffic......

Also agree 100% with Dieselcon above, run the car at varying rpms as described ....... It applies to every engine......

Paralize
13-05-12, 07:01 PM
Varying rpms is the only way a person can drive in Sydney, with all the Toll Road (Mx crap) bad roads, narrow streets, big trucks, Sunday drivers... list goes on..

Yeah auto.. (never owned an auto b4)

Load.. hm... how about, how may people can fit in a Jeep Wrangler 2 door and traverse the windy roads to wombean caves? + or - barf bags.. your choice..


Cheers,

Linda