slw210

Hi Mileage oils are semi-synthetic (synthetic blends) and specially formulated to keep older gaskets and seals in great condition. I run Hi Mileage in the Suburban. 5W-30.

I run full synthetic in the Broncos and the daughters Mustang, I will never run conventional again.

I run Castrol or Valvoline brands, but most likely any brand will be close.

The only CON to running Synthetics and synthetic blends is the initial cost. They last much longer than conventional and I get better mileage, so cost will work out to not much difference.


That sounds opposite, the w (Winter) is the below 32°F rating, you should run the lower in the winter time and running 5w in the summer is no different than 10w because above freezing the 30 is the rating that matters.

Cpb200

well i run 15w 40 shell rotella oil in my truck its a 99 with 260000 miles of course its a 6.0 so bigger engine means heaveier oil and i live in louisiana where its always hot but sence its still running great and i still pull with it i guess i did somthing right

slw210

Bigger engine doesn't mean heavier oil. Specs for a 99 6.0 is 5w30. Give it some 5w30 hi mileage blend and you can tell the difference.

Christopher Krumholt

Im in Baton Rouge.

I went with a 5W30 Mobile 1 synthetic. AutoZone had a sale on 5QT jug for 32 dollars and you get the oil filter for free. Only bad think I had to buy 1xtra qt to make it 6 and that was like 8 dollars. I have heard that Mobile is the best right above lucas. One guy told me that he thinks he noticed an increase in MPG.

Thanks for all the replies

nkh34

after 160,000 my family uses 5w-30 castrol gtx high mileage and it seems to work great for us its reasonabley priced and my truck loves it

cleveland63b

its all matter of opinion...my only input is that if you pay attention and change it like you should then you should be fine. As far as synthetic or not, if your oil pressure is good and you have no leaks of any kind its up to you but if you have leaks or low pressure using synthetic will make it worse.

I've seen many times where people have a small non bothersome leak and switch to synthetic and the leak gets worse-smaller molecules=bigger leaks just something to keep in mind

nkh34

See i had a small leak on my civic it was little never even had to put more in between changes like 3 drops a night and the jerk off lube tech put synthetic in said "it was gonna patch that little hole right up" and then it was taking a bottle a week before my 3000 was up and he said that it must have been worse then he thought now i dont even drive the car because i have to park it on the street for the snowplows to manuever around. thanks for that nice peice of knowledge ill remember that for sure

cleveland63b

no problem, theres a lot of little known facts about synthetics...the commercials and brochures make them sound so amazing but theres always other circumstances

Just like being able to go longer on oil changes, as long as the vehicle is running good with no contaminations of any kind in your engine and you still change the filter sure I'd agree but it doesn't take much for oil to get diluted with gas or the like and of course filters don't last forever. Just my opinions