Auto with 3.42 mpgs?
Thread Starter
Instructor
Joined: Jan 2008
Posts: 235
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From: East TX
Auto with 3.42 mpgs?
I recently had my t56 pulled and went with an rpm built 4L60E along with a 3200 stall. It looks like my mileage is cut in half. The car has LT's, no cats, A&A, custom tune, etc. I've been doing all city driving while just cruising, no WOT runs. I just filled up and I only avg'd 12.7 MPGs. I was around 16-18 in the city with the t56. Do the numbers add up or do I need to have my tune looked over?
Thanks
Jerrad
Thanks
Jerrad
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The change in rear gearing should not drop your MPGs that much. But your mileage can vary with each fill-up depending on a lot of factors - traffic patterns, route taken (hilly, lots of stop lights, etc.), and the weather. I'd check the MPG for a couple of more tanks before deciding that something is wrong. Another thing to consider is a manual tranny car typically will get better gas mileage than an auto tranny - at least my '00, which was a 6-speed car, got better MPGs than my '03 A4 car gets.
Instructor
Joined: Apr 2005
Posts: 241
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From: Arlington Texas
I recently had my t56 pulled and went with an rpm built 4L60E along with a 3200 stall. It looks like my mileage is cut in half. The car has LT's, no cats, A&A, custom tune, etc. I've been doing all city driving while just cruising, no WOT runs. I just filled up and I only avg'd 12.7 MPGs. I was around 16-18 in the city with the t56. Do the numbers add up or do I need to have my tune looked over?
Thanks
Jerrad
Thanks
Jerrad
Team Owner
Joined: Jan 2007
Posts: 29,065
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From: cookeville tennessee
The change in rear gearing should not drop your MPGs that much. But your mileage can vary with each fill-up depending on a lot of factors - traffic patterns, route taken (hilly, lots of stop lights, etc.), and the weather. I'd check the MPG for a couple of more tanks before deciding that something is wrong. Another thing to consider is a manual tranny car typically will get better gas mileage than an auto tranny - at least my '00, which was a 6-speed car, got better MPGs than my '03 A4 car gets.
To the OP here I wish I got 12.7 in town with my auto and 3:42 rear gear.
Thread Starter
Instructor
Joined: Jan 2008
Posts: 235
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From: East TX
I'll do a few more tanks and see where I'm at.
thanks everyone
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Joined: Aug 2011
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From: Portland OR
My cam, heads etc A4 with 3600 stall and 3.42 gets 14mpg in typical stop and go driving. On weeks where the traffic is light, that goes up to 16mpg. My commute is 90% freeway, but at least half the time it's a parking lot.
MPG on the highway at 73 mph is 25.
I'm not fully tuned yet, the DFCO (decel fuel cutoff) is still turned off.
In stop and go, the converter is what sucks the mileage down.
BTW....these readings are from the DIC which has proven to be quite accurate.
Ron
MPG on the highway at 73 mph is 25.
I'm not fully tuned yet, the DFCO (decel fuel cutoff) is still turned off.
In stop and go, the converter is what sucks the mileage down.
BTW....these readings are from the DIC which has proven to be quite accurate.
Ron
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Thread Starter
Instructor
Joined: Jan 2008
Posts: 235
Likes: 0
From: East TX
My cam, heads etc A4 with 3600 stall and 3.42 gets 14mpg in typical stop and go driving. On weeks where the traffic is light, that goes up to 16mpg. My commute is 90% freeway, but at least half the time it's a parking lot.
MPG on the highway at 73 mph is 25.
I'm not fully tuned yet, the DFCO (decel fuel cutoff) is still turned off.
In stop and go, the converter is what sucks the mileage down.
BTW....these readings are from the DIC which has proven to be quite accurate.
Ron
MPG on the highway at 73 mph is 25.
I'm not fully tuned yet, the DFCO (decel fuel cutoff) is still turned off.
In stop and go, the converter is what sucks the mileage down.
BTW....these readings are from the DIC which has proven to be quite accurate.
Ron
guess I'm not too far from the norm.
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Don't forget too that the Automatic has a much lower overdrive ratio than does the M6. It's significant. Not only does the motor twist more, but it does it at a point where fuel economy is terrible. My A4 car (w/3.15s) gets about 4-5mpg more at 60mph than it does at 75. First car I ever owned where that was the case. I'd almost say my M6 car is opposite. Maybe not 4mpg, but close.