What oil do I use?
New User
Joined: Nov 2011
Posts: 9
Likes: 0
What Oil
Synthetic oil making motors leak is a myth.
True when they first started to put synthetic oils in motors years ago it did make the seals shrink. That was quickly fixed.
I have been using synthetic in all my vehicles. with no problem regardless of mileage. Oil is cheaper than motors so put in the best I can buy.
True when they first started to put synthetic oils in motors years ago it did make the seals shrink. That was quickly fixed.
I have been using synthetic in all my vehicles. with no problem regardless of mileage. Oil is cheaper than motors so put in the best I can buy.
Senior User
Joined: Dec 2010
Posts: 203
Likes: 1
From: Middle of nowhere, Mo
Right another thing ppl don't know is there isn't that big of a diff in the 5w30 and the 10w30 the 5w30 at cold temp viscosity is 10.6 and the 10w30 at cold temp viscosity is 10.5. Yes you read that right the 10w30 is actually thinner at I believe 32 degrees but the 5w30 in a much much colder weather will be thinner
Cargo Master
Joined: Jul 2011
Posts: 2,000
Likes: 4
From: Nowthen, MN
I think you guys are overthinking this. We're talking about a 21 year old truck with 200,000 miles on it. Honestly, I would just put conventional 10w30 in it and be done. Even today's cheap conventional oils have a much better service rating than was recommended for that engine back in 1990.
If we were talking about something newer with low miles, I would say go synthetic.
If we were talking about something newer with low miles, I would say go synthetic.
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Postmaster
Joined: Dec 2007
Posts: 3,052
Likes: 1
From: Jacksonville FL
I run Mobil 1 extended performance 15k mile oil with M1 EP filter and change at 10k.
I also put it in my dads 07 F150 and moms 05 avalon and change at 15k.
Oil has come a long way and I personally feel changing at 3000k miles is wayyy too early.
Senior User
Joined: May 2011
Posts: 497
Likes: 0
From: Morgantown, WV
when I first bought my truck, one of the first things I did was change the oil and used Valvoline full synthetic and my oil pressure gauge was reading funny the whole time I had it. I changed it to the Motorcraft synthetic blend and wasn't happy with that either. I just use Valvoline high mileage 5w30 in winter and 10w30 in summer. I think when these engines were designed, they weren't designed to run on synthetic so I just stick to what the manual says.
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
This is not true. I had two trucks with 100k+ on them when I started using mobil 1 full synthetic. Neither leaked a drop before I changed. Within six months, both developed serious leaks. I was losing almost 2 quarts between changes.
