: Gas mileage change

12-11-11, 10:00 AM
Had my 07 ESV back for about 1000 miles after the transmission was serviced. Took it in for hard shifting. They replaced some seals inside and reflashed it. Before I took it in I averaged 16-17 in town. Since I got it back I'm only getting 12-13 mpg. Same gas, same drive. Any ideas?

Cadillac Cust Svc
12-12-11, 08:21 AM
The estimated EPA is 12 mpg city and 19 mpg highway with a combined EPA of 14 mpg. So, the numbers you are getting now are around what they should be. If you want to you could always contact the dealer where you had the work done and see if this is normal for the type of work that they did.
Cadillac Customer Service

12-12-11, 08:24 AM
May have had the battery disconnected and the mileage reset itself and if you are in a cold area they have switched to winter fuel which is worse mileage than the summer blend, just somethings it maybe

12-21-11, 05:25 PM
Remember, the transmission probably has to relearn your driving habits which must be extrodiarily good and cause fast upshifts. I would give it a week and then try another test.

12-21-11, 06:58 PM
Are you going by the DIC? Figure it out on paper, the figures maybe different

12-22-11, 07:45 AM
Are you going by the DIC? Figure it out on paper, the figures maybe different

Agreed. I find the computer to be way off sometimes and right on other times.
The other day i filled up my ESV. Computer told me I had use 26 gallons and I put in 24 according to the pump.
Pump could be way off too i suppose. I can't help but wonder if those are regulated in any way.

12-22-11, 08:44 PM
I figure the MPG by hand. The mileage has come up to 13.9 over the past few weeks. Maybe it is relearning my driving style since the tranny reset.