Just picked up some Castrol 5W 50 synthetic for a song. I have been running 5/10W-30 synthetic for the longest time. Anybody ever use 5W 50? Any potential issues - should I hand this off to my buddy for his ford ?
Not the worst thing in the world as long as your temperatures are relatively high right now. You will probably get a slight mpg loss. I personally would not go higher than 40, but I know there are people running xw50 on this board.
IS the 5w-50 fully synthetic? If so, you'll be fine. I use the mobil1 5w-40 full synth and have stuck with it now for close to a year now. Pulled the VC off about a month ago and things were incredibly clean in there. Car has 121K miles
I got leaks from the rear seals of my engine when I switched to synthetic. I would actually call it a mix between a seep and a leak. I started with 5w30 mobil1 and got a lot of leaking in the beginning and then it tailed off. I just put in 0w40, and had a small amount of leak/seepage the night of the change, but since then have not really had anything but a little seepage. If your engine/seals are not terribly old, I have read that when you switch to synthetic you will often get leaking, then seeping, then if lucky just a little weeping.