Scoobydoo1974

I need conformation.
I recently bought a 2007 Silerado (new body style) from a friend of mine.It has 212500 on it. My friend has always had the oil changed every 3000 miles. When i got the truck i noticed on the sticker from the oil place he has used that they had used Castrol 10W-40. So i thought these trucks use 10W-30.
So like i always do i changed the oil using synthetic 10W-30.
I knew before i bought the truck that it smoked sometimes and it would drip a Couple of drops of oil in the driveway.After the fresh oil change i ran the truck about 700 miles. I have not seen it smoke anymore but now it leaves puddles of oil on my driveway. The oil seems to be coming from the rear main seal.
My thoughts are that the new synthetic oil fixed the valve seals and the blue smoke stopped but it also cleaned the crankcase and main the leak worst.
I am mechanically inclined and can pull the tranny and replace the seal but would like to hear if i am right about using a different oil.
Any thoughts??

oilcanhenry

Scotty Kilmer swears by a product called AT-205 for leaking seals. I haven't tried it but it might work. You have to realize at 212k you are going to have issues like this to contend with at that kind of mileage..

Scoobydoo1974

I understand about the high mileage on the engine but i have had a couple of the same trucks one close to 300k miles anotherone with over 300kmiles
With no problems at all. I just do the regular maintenance on them.
But again i bought them new so i know what ticks on them. I also know that not all engines work the same. On one of my trucks when first bought it after 8k miles it started knocking, the dealership took care of that.
So i guess that no matter how good you take care of a vehicle there will be something that is eventually going to fail

oilcanhenry

That is true. Some part may have neen manufactured out of spec or may have susdained damage of another kind. No vehicle sats forever without some work.