High mileage company car


Staff member
The Motor City
Are you sure the 5W-20 previously used was dino? I have the impression most modern 5W-20 oils are semi-synthetic, bacuase it's hard to make a 5W-20 from dino and not have problems with oil loss from vaporization. Engine cleanliness may be from using a semi-synthetic oil.


Buffalo, NY
Vulcan 3.0's are tough little engines. I'd be more concerned about the transaxle. Is it original? How's the ATF look? AX4S/AX4N's usually nasty up a sump of Mercon-V every 30-40Kmi. Joel
Yes original tranny. When I first got the car the tranny was not shifting well kind of jumping around. I had the tranny flushed and a new filter installed with new fluid. Since then it has run very well with smooth shifts.
I am in charge of quality control for a company located in three states. They gave me a 2000 ford taurus wagon with 165000 miles on the clock. It has the 3.0 ohv six banger. The oil was not changed in six months so that was my first mission. I went with havoline 10w-30 at 5000 mile intervals since all of my driving is long highway miles. To date the car has 178000 mies on the clock which have been loged since Sept. 5, 2005. I experienced no oil consumption with the havoline at the stated intervals. The mileage would run 26 to 28 mpg. Just for kicks on the last interval I filled with Carquest 5w-30 and ran a shorter 4000 mile interval since it was winter time. The car used one quarter quart in the interval. Upon changing out the carquest I noticed the oil did not turn nearly as black as the havoline did. I am not saying the carquest was bad oil it was just a interesting observation. The car ran just as good with the carquest as the havoline and produced the same mileage. I think the motor will last to 250000 mile or further. It was just interesting that the carqest oil did a good job much like the havoline has. Yes it is made by Valvoline. Another obsevation, I removed the PVC from the valve cover to check the deposit level. No sludge just fine film of deposit not heavy at all. The car was run with 5w-20 before I got hold of it. Granted all interstate miles will make a big difference in engine life. Just another example the dino oil will work well for long engine life.
Portland, OR
Well I too own a 2001 Taurus with the Vulcan engine. It has 90K miles and does not use any oil in between changes. I bought it used at a dealereship, so I can't say for sure what oil was in it when I bought it. After owning it for about 6 months, I changed the oil. I used Valvoline 5W20. Why would you use a thicker oil, like 10W30 (well it's thicker when cold). I mean these engines are pretty tight, and if it's not using any oil then it probably is tighgt in there. 10W30 is thicker on start up so it won't flow as well. Oh yea it's also thicker when warm. What made you go with 10W30?
Well I had no idea how the engine would respond to any oil when I was given the car. I thought the 10w- would offer a little more shear stability because of the hot weather at that time. It was just a guess. Now it hardly uses any oil with the 5w-30. I think 5w-20 might be a tad thin with this high of mileage but again that is just a guess. I am no expert. [Smile]