synthetic oil

[Kevinh]

Anyone hear that you should not switch from regular oil to synthetic, you could damage the motor. Is my mechanic sniffing too much used oil. Thanks Kevinh

[TSR53]

He's right and not right. Sometimes [depending on engine, mileage, wear, condition of seals, climate, age, etc] when you DO switch from regular oil to synthetic oil your seals *might* start leaking. I've experienced this on occasion with one of my Porsche 944's all alloy engine. Amazingly, the leaks stopped when I switched from Mobil 1 to Amsoil 15-40w HD diesel/marine oil. The *key* to this of course is Amsoil's description of "modern vehicles".

From Amsoil's website... [link]

Q. Is it true that installing AMSOIL or other synthetic oils will cause my engine to leak oil?

A. In modern vehicles, there is no risk of AMSOIL motor oil leaking. In fact, AMSOIL motor oil is fully compatible with modern seal materials. It is properly formulated to condition seals, keeping them pliable to prevent leakage.

[edit - additional link and FAQs from Amsoil]

[singingcamel]

have some specs on this sight.
www.singingcamel.com

[landrover77]

synthetic oil

For a 1995 discovery that leaks a bit as it is, is it a good idea?
Switching from a pennzoil 10w-40 to a mobil 1 synthetic.
Is the car too old for changing to a synthetic or would it help it perform?

[Mudley N. Grimey]

Everybody I have talked to says that there is NO adverse side effects to swithching to synthetic oil. Be aware that some "synthetics" are not true synthetics, but highly refined mineral oil. Mobil 1 and Red Line are true synthetics. Besides that, most older Rovers leak already, so it's not a serious issue.

I switched to Mobil 1 in my Disco I with no adverse effects at 100 K mi. and no other changes except an increase in fuel mileage.

When I changed to Mobil 1 in my '92 Chev 454 SS, my mileage improved and my oil usage actually decreased, when towing, as there was less oil burnoff from the cylinder walls.