Dealer says, "Don't switch to synthetic oil!"

[m3f_marked23]

My '97 M3 automatic (88k miles) supposedly came stock with normal oil. My service advisor says that it's not a great idea to switch to synthetic so late in the car's life.



He says that when folks switch to synthetic, the VANOS may begin to leak. He didn't offer any good explaination for why this happens. I can't imagine why he'd tell me to stick to normal (cheaper) oil, when I wanted to go with the more expensive stuff... So I tend to imagine that he's not BSing me.



Has anybody heard of this?



-Mark

[m3f_ESP_5b942e8837]

from what I understand the chemical composition of the 2 oils is different enough that it can/does have an impact on the gaskets, seals, etc... the leakage is caused by the synthetic oil causing seals to shrink.



just what I have heard... I have also heard that after a few thousand miles it will stop leaking... I have switched higher mileage engines from natural to blends and had no leaking problems, not sure who makes blends now though.

[m3f_M3BOUND]

There are still alot of misconceptions about synthetic oil and gaskets etc that are not true and it sounds like your dealer may be feeding them. Not all service advisors are that knowlegable but they like to sound the part. I would do some research to ease your concerns. I would not hesistate to change to gain all of the benefits of synthetic.

[m3f_ARC M Power]

my dealer suggested me to switch to synthetic and he said all M engines are supposed to use synthetic, but in the earlier models, they will only put in synthetic upon customers' request. I switched cuz i found that on my 97 there was oil burning with normal oil, but it works perfectly fine with synthetic.

[m3f_Roadrunner_00430f3330]

i've always been told to use syn..............hmmm...but on a car that's been on regular most of it's life @88k miles, not 100% sure. he could be right, kinda..maybe a little if the car was always mantained w/ normal oil. have the records pulled and see. again, i'm not 100% sure on this but i heard similar comments.

[m3f_M.Adair]

I agree with ESP. When I had my Milano 3.0 I switched to synthetic in both the motor and the trans. Lots of expansion and contraction on Alfa motors. I definitely started to get leakage around some seals and gaskets. The stuff is definitely got a different composition to it. No question it is the better protector but I have seen this issue more than once. Keep checking!

[m3f_JAlfredPru_7f28a4f655]

i may be wrong here...



but ive heard that when a car starts leaking on syn oil, its due to the lower viscosity of the syn oil and should be switched back to regular



u might wanna replace ur engine's gaskets if u want to switch to syn oil??