April Gas

I filled up the caravan on Monday with 87 octane (no ethanol). I will no longer be using 91 octane because I didn't see an improvement in mileage.

April 23: 266.7 miles / 13.6 gallons = 19.6 mpg

Caravan odometer = 178,744 miles

Tire Pressure, part 2

Part 1 here. The owner of a tire store came into the liquor store where I work, and I struck up a conversation with him. I asked him if I should follow the tire sidewall (44 psi) or the driver's door (35 psi) recommendation. He said if I put in the max pressure, the tires will wear out in the center, so I should use 35 psi. It will be a smoother ride with better MPG, and the tires will last longer. The only time I should use max tire pressure is if I have a heavy cargo load, which I rarely do. I don't even have the middle and back seats in the van.

This is a different opinion from my mechanic (who also services tires) who said I should use the tire sidewall recommendation for longer tire life and better MPG. So now I have two knowledgeable people with different views on tire pressure.

Should I stick with 35 psi, inflate to 42-44 psi, or split the difference and go with 37-39 psi?

Gas and Tire Pressure

Another fill-up using 91 octane at a Sinclair station:

March 13:
261.8 miles / 14.032 gallons = 18.66 mpg

I don't know what to think about this stat. On one hand, it's pretty good mileage for winter. But on the other hand, it's been a mild winter, and it's 91 octane! 91 octane was $3.909 a gallon. If I don't start seeing 22+ mpg with 91 octane, I'm going back to 87 octane at a Cenex station.

One possible reason for the lower-than-expected mileage would be the tire pressure on the new tires I recently purchased. I like to have my tires at 40-44 psi (max load on tire sidewall is 44 psi). The mechanic or technician might have set the tires at 35 psi, which is what the tire pressure placard on the driver's door recommends.

(5 minute break)

I just went outside and checked the tire pressure, and the tires were indeed set at 35 psi. Boy, the one time I go to a different mechanic...

Yes, the ride is a little smoother at 35 psi, but I'd rather have higher MPG and longer tire life (more even tire wear at 40-44 psi).

Caravan odometer = 178,422 miles

Boring Winter

Sorry for the lack of updates. I have been trying to limit my driving to save money. Nothing has gone awry or afoul or askew lately, so that's a plus.

Caravan odometer = 178,280 miles

Wintervention

The caravan should now be ready for winter. I bought 4 Firestone Touring P205/70R15 S95 tires (with mount, balance, and alignment), and installed a new 18" rear wiper.

I filled the gas tank with 91 octane (no ethanol) again.

January 23:
137.3 miles / 7.919 gallons = 17.3 mpg (Note: It has been a lot colder since my last fill-up.)

Caravan odometer = 178,160 miles

The Van is Back.

In my last post, blogger "have a nice day" pretty much described the repair work my mechanic performed better than I could have described, so read his comment.

Other information:

1. The oil pressure sender was replaced because it was leaking oil.

2. I have switched from Valvoline synthetic blend 5w-30 to Valvoline synthetic 5w-30. I have had problems finding the synthetic blend recently, so I thought now would be a good time to make the switch to full synthetic.

3. Lastly, I filled up with 91 octane (no ethanol) after getting the caravan back from the shop. I won't be doing this very often, but I thought it would be interesting to see any differences in performance compared to the 89 octane (10% ethanol) and 87 octane (no ethanol).

The following fill-up was achieved with 87 octane (no ethanol):

December 27:
277.9 miles / 13.935 gallons = 19.94 mpg

Bad News Update

According to my mechanic, the caravan has a blown head gasket. I looked around for pricing on replacing the motor, but it would be cheaper to do the repair work instead of buying a new engine block. Since the valve covers tend to go bad on the 3.0L caravans, I will be replacing those as well. Fortunately, I won't need to buy new cylinder heads; just get them milled.

Please excuse any possible terminology errors, for I am not car savvy enough to have in-depth engine discussions.