djhives

Hi Pals,

I have a '92 5.0 EFI with about 145K on it. It seems to have been taken care of all it's life. Runs strong.

My question. Is it beneficial at this stage in the game to switch to full synthetic oil? And please SHARE YOUR PERSONAL STORIES of switching over 'mid life' to full synthetic oil from regular oil. Any issues? Benefits?

It's used as a delivery vehichle and I drive like an old lady so the idea behind me swtiching over is to maximize it's service life. It's not a 'daily driver'. Id say less that 2k miles per year.


Thanks ALL - great forum here

Execut1ve

sounds like synthetic could be beneficial to you, with how few miles you put on it you could really take advantage of the extended oil change interval and change it once or twice a year. I'm thinking of going with synthetic in my '94 5.0L once I get my oil leaks sorted out

djhives

Let me guess your oil pan is leaking? I had the same problem and found an excellent fix that avoided removing the oil pan / lifiting the entire engine...

My oil was leaking on the exaust pipe below giving a burnt oil smell, thats how bad it was... Ill tell you the fix if you wanna know...



Anyway -- you know how peple say not to switch to synthetic after a certain ammount of mileage, is this true in your op or just an old wives tale... do you use sythetic in your 5.0??

Execut1ve

I don't yet, but I've had it for less than 3k mi. It is leaking from the rear main seal and oil pan gasket. I even have the same burnt oil smell!

I think it is a wives tale... you won't see the same benefits as if you had been using synthetic from the beginning, but it'll be better than conventional. From my reading on Bob Is The Oil Guy, synthetic oils are thinner at cold startup temps than conventional oils of the same grade. This reduces engine wear on cold startups which has been said to cause 90% of all engine wear.

djhives

Ok then... since you say its OK, on mah next oil change Im going to go with the Mobil1 Exteneded Performance 15,000m/1 year oil. I use that in my 91 miata - but I want sure about such a big engine like the 5.0


As far as your leak goes, if you are getting the typical leak on the exhaust pipe that smells like burn oil especially when you get to a stop light... well I'm almost 99% sure its NOT your rear main seal leaking.


These 5.0 oil pans from this vintage seem to like to shamrock their gaskets out of their proper positions for no good reason.


I was pissing oil. I had to check and fill the level DAILY.

So one day I got her on ramps. I drained the oil and shot brake cleaner all over the pan gasket area until it was as clean as I could get. Then I gunked a HEAP of permatex "RIGHT STUFF" all around the flange. I let it set 24 hours. THen sprayed it with permatex copper spray-a-gasket.

Bone dry since!

Yes the 'proper' thing to do is pull the engine and change the pan.. but its not practical either. This 'right stuff' sealant is gnarly. It dries like a rock and repels oil like nothing else.


heres some pix of what I did:







Not pretty, but damn effective...

Note how it APPEARS to be around the rear seal area.... but trust me... I thought my rear was leaking... nope.. just the pan which is apprently notirious for leaking...

just some info that may or may not help you...

--hives

azjeff

IMO I would not switch. Especially with such few miles you put on the truck per year. You don't change oil strictly on mileage IIRC. I picked up my F150 with 98k miles...had no leaks. Was thinking same as you, synthetic is better... I should treat the truck to the best. Well, I developed a pan gasket leak right after. It is minor enough for me to just watch and top up if necessary. I went back to 10w-30. This is not some super high performance hi tech engine we are talking about here. I think a lot of people tend to get a bit OCD about their engines in vehicles. It seems that as long as you change the oil at suitable intervals you are going to get as much use out of your vehicle as you could possibly want. JMO mind you!

Execut1ve

It's your call to make, I'll be switching to synthetic in my truck to make the cold starts easier. it definitely struggles cranking up in the cold ohio winters

Warlockk

Here is a little info on Synthetic oil. I was working as a service writer at Toyota. They are big into the mpg war now and decided to switch to all synthetics (motor oil, trans etc) Toyota has been able to get as much as 5 additional mpg on their vehicles with this simple change. Also they extended the recommended service interval. Synthetic motor oil has molecular chains of a more uniform size than standard. This means you get a more even sheer, easier poor and higher thermal viscosity. The only problem with changing in a high millage engine is due to the thinner pour and generally better cleaning additives you find small leaks that the standard oil doesn't. But hey if its leaking it needs fixing anyway right. I changed my 03 focus and picked up about 2mpg. Didnt notice any real difference on my 1990 f150 but its still a project in work. I did however notice less deposits at oil changes and when I open the engine up.

djhives

AZJEFF ---


You make a valid point... as this is not my 'play vehicle'.... but you make a point... since i dont drive it much, synthetic oil becomes a moot point.....


thank you

djhives

Exec.,


You make a good point as well... cold starts will be an issue since I dont drive it (and thus start it) as often....


hmmm