Skip to main content ↑ ↓
Topic: Poor Gas Mileage (Read 2067 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Re: Poor Gas Mileage

Reply #25 –
Yahoo Message Number: 57071
Mike:

Your switch from regular engine oil to synthetic improved your mileage by 12.5% which is really great but at what cost? How often did you change the regular oil and how often do you change the synthetic oil and what is the cost for the synthetic? Country Coach and Cat advised to change regular oil annually.
I have asked two Amzoil dealers what their advice is and they say change it annually too. It would seem to me that the synthetic should last longer since it is more stable and heat resistant.
Bob

2005 Inspire 51394
Auburn, CA

Re: Poor Gas Mileage

Reply #26 –
Yahoo Message Number: 57072
Jack,

In all the discussion that followed your question about poor gas mileage, I may have missed seeing someone suggest that poor mileage can be caused by a bad fan controller which keeps the hydralic cooling fan running at full speed. Are your engine temps always below an approximate 190-205 range, i.e., fan overcools the engine. When parked with the A/C off, and the engine running, will the fan hold a 8.5x11 sheet of paper against the grill -- i.e., running at full speed? Both are signs that a portion of the engine power is going to the hydralic pump, and reducing your MPG -- approx one MPG.

Herb

2007 Allure 430 #31466
Forum Moderator

Re: Poor Gas Mileage

Reply #27 –
Yahoo Message Number: 57073
Jack,

The C9 Cat went thru a number of different ECM programs in an effort to improve economy and drivability. We previously had an '06 Inspire with C9 and within the first 12 months Cat changed the program 4 times. A re-flash to the latest (at the time) certainly helped.

coriwelsh

08 Allure 31611 with ISL power

Re: Poor Gas Mileage

Reply #28 –
Yahoo Message Number: 57105
Bob,

Every 6 - 12K or so (depends on how much I use it in a year) I pull a sample and send it in for analysis. If OK, I then replace the Gulf Coast Bypass Filter I have and replace only the 6 quarts lost doing that. It's enough to replenish additives and get a fresh filter in. So far, the lab analysis has always been very good and didn't even require the 6 quart update - but I do that anyway. The oil is about $6-7 per quart depending on where I get it. The lab analysis is around $20. Has varied over the years.

I documented my entire procedure in a previous writeup.

Mike Cebula
'95 Magna 5266
 

Poor Gas Mileage

Reply #29 –
Yahoo Message Number: 57009
I had to comment on the mileage results of everybody. I think there are two major factors:

1.------- Relax enjoy your coach and set the cruise at about 55 MPH, DO NOT GO OVER 60 ---- MILEAGE PLUMMETS

2. ------- Hurry up and get to 50,000 plus miles. We have 65,000 miles and I can see the improvement in the performance of the Engine/Trans.

Stan Canaris Inspire 2005 --- 51406

Begin forwarded message: