Better mileage after breakin?

2010 AC 2.7 5spd 4x4 SR5.... just about to roll over 3000 kms total, mostly (90%) City driving... 18.5 mpg average, running premium fuel and stock tire psi... do these things loosen up?

 

Yes, and the performance will get better also, it was like a totally different truck when i hit 25k miles.

 

It will get better. I never used premium, and it went up to around 20 mpg (combined driving).

 

yes. I used premium for a bit too. Seems mine really picked up after the 30k spark plug change and changing the diffs to Mobil1 full synth. I run Mobil 1 full synthetic motor oil too. I usually got around 17-19, now I get around 20-21, and if I run it hard it rarely runs less than 19.5. Speedo is 47k now. And yes, I check mine to the T every fill up, still have the logs of all my fill-ups.

 

My 2010 2.7 AC 4x4 is up to 11,000 miles now with an average MPG for those 11k miles right at 21.48 MPG. I can't say my milage has improved dramatically beyond the first 3000 miles. I use the iPhone app to track my milage and often get close to 22 but averages between 21 and 22.5 are typical and seem to depend more on type of driving than break-in phase.

Good luck,

 

Yes the mpg get better. My 2006 AC 2.7 auto was getting 22mpg one year ago with 41k on the clock. Now it has over 50k and the last 2 tanks have averaged 25.5mpg. I drive like a sissy but that has not changed since 1996. Maybe I'm used to it and know how to drive it better, maybe the original owner did short trips and the carbon is finally clearing out (I do 80% highway), maybe it's still breaking in. But it's getting better fo sho.

 

thanks for the input guys...

 

I didn't notice MPG improvement, but the transmission and engine smoothed out around 40k miles. Engine seemed to idle smoother, and I could run slower speeds in 6th gear like it had more power. I was running 285 tires for a year or two and lost a bit of torque. After the 40k mark it seemed I'd gotten that torque back and no longer needed to downshift or step on the gas as much for hills. I could even accelerate up steep grades at 30mph in 6th gear. Shifting also smoothed out around the same time too.

I didn't notice any mpg improvement until I swapped the air filter with an AFE Pro Dry. Went from 17-18mpg average to 20mpg average, all with mixed driving.

 

Mine has gotten a little better over 7500 miles.

 

30mph in 6th gear up a steep grade? That's a lot of torque, at really low RPMs. Sure it's not a diesel?

 

I was surprised too. It's a rather steep hill coming out a of a valley. Speed limit was 30, and it was slowly rising to 35. I looked down thinking I was in 6th and that couldn't be right.... Popped it out of gear, and sure enough it was all the way over to 6th.

 

I track mine carefully, I was averaging 22.5 with 87, and I get 23.5 with 89.