Just wondering if anyone is using synthetic oil and if so what you have experienced. I have 148,000 on my 302 and as far as I know it has never been apart. The oil pressure tends to stay right at the N-O range on the oil gage which seems low to me. I have been changing the oil every 2500 miles and using Valvoline Maxlife (recommended for 75000 mile and above motors) since I bought the truck a year ago. There is some blowby and some moisture in the oil (evident on the top of the dipstick and oil fill cap, not milky oil) in the winter time here in Michigan. I was told that was normal for a high milage 302 truck motor. I was thinking of switching to Mobil 1, Amsoil or Royal Purple and was just wondering if anyone else has tried either of these products and if there were any drawbacks.

 

I have used 20w-50 with great luck in my high mileage Bronco, non synthetic. I've read posts where people are either starting to leak, or lose oil somewhere when they start using Synthetics in high mileage engines. Im sure someone who knows what they are talking about will post in return to your questions though.

 

The thing to watch out for with 100% synthetics is their cleaning capabilities especially in a high mileage engine. 100% Synthetics will eat and clear away deposits and sludge very well leaving that little damp spot dripping or constantly seeping if you have any. It will clean the crud out but if any of that crud is blocking potential leaks, you will find out where.

 

I have 150K+ miles on my 89, 302 and have been using Pennzoil's Blended oil for some time - it's the one in the clear container, and has some notation as to be used for Trucks, 4x4's etc. I use the 15W45 in my engine. I have been using the blended 20W40 in my 73 VW bus for years with good luck.

This stuff is supposed to hold together better under high temp conditions, such as the air-cooled VW engine. This stuff doesn't break down all the old gunk inside the engine as much as the pure synthetic types - and - another big plus to me - the blends are cheaper - less that $2/qt at Wal-Mart.

Regarding your oil press Gage, I think I've read here in the past that these gages don't actually read the actual pressure, only that they move the Gage needle when there is so much oil press available - 10 lbs, perhaps. Kind of a go, no-go indicator - either you have pressure or not, and not how much...

 

i had the same problem. a freind who has been working on cars for 30 years said that ford v8's always have some moisture because of short trip driving. my bronco has 130,000 miles. it built up a gray goo at the return line that goes into the air filter. he put in a can of 5 min. engine flush when he drained the oil it was the blackest i have ever seen. he had me change over to 20w50 oil. he said to run this for a month than change the oil again. it worked, i now go 3000 miles and the oil is only 1/2 qt low. he said that the moisture and the oil can cause a clay like buildup around rings and at the oil pump screen also this goo will clog up the pcv valve. the oil pressure relif valve can clog and put a lot more pressure inside the motor and cause a lot of blowby into the air filter. i hope this helps. i know the old bronco is running great. ed