ok so my xj has 188000 miles on it and ive only put 3000 miles on it since i got it and its time for an oil change. i went to check my oil level the other day and the oil was like stuck to the dipstick in the sence that when i pulled the stick out the oil literally poured off. ive been using Rotella shell (has zinc in it) 15 w 40 i think...

i just want to know if its better to go with high milage, what weight, and if i should use full synthetic or what?

 

the idea behind syn. oil is that new engines are so well made (in the sence that they seal VERY well) that there are no gaps for such a light oil to escape from. id stick with a regular oil. ive heard so many mixed reviews on which oil to use; penzoil, amsoil, mobil... idk... i usually go be price, somewhere middle of the road. if your usuing a thick oil such as a 15w 40 then there may be some excess oil on dipstick. was engine hot or cold? have you tried draining oil to see if there is something in there that doesnt belong? idk about that zinc addative, maybe im not versed in oil well enough... i usually run a 10w 30 hot the heat and a 5w 20when she gets colder (which is now) my .02!!!


EDIT- if any of the info about syn oil is incorrect or whatever, please let me know!!!!! thanks!

 

Synthetic doesn't need a new engine to not leak. Just good seals. My 90 with 5-30 syn doesn't leak a bit. Synthetic is a far superior lubricant. As far as viscosity goes I'm really tired of trying explaining but I will say you never need thicker then 5-30. If you want to learn about oil go to www.bobistheoilguy.com and check out motor oil university. Anyhow I would switch to synthetic and never look back. FAR SUPERIOR.

 

You sure don't need 15w-40 in it. Either a 10w-30 or a 5w-30 is all that's needed. Thicker oil will hurt a motor. If you have a diesil thick oil is made for that.

 

I use 10-30 synthetic. Mobile 1, to be specific.

And I have an 87.

 

the engine was cold and i just did an oil change and it didnt seem like anything was wrong with the oil

 

well from what you guys say im going to use synthetic. but in jersey its about 30 in the winter and 90 in the summer so what weight can i use that i can stick with year round?

 

I'm up in northern Canada where we've seen -57c so I use a lighter oil in the winter.

 

5-30 syn is a great all around oil.

 

Jeez guy they all have said it 5w-30 or 10w-30.

 

i understand that i just wanted to narrow it to one kind... thanks though... 10 30 looks good for me