Up until '83 our cars had solid rubber motor mounts and in many cases they are still in place today with no problem. The concept of fluid filled MM's was a good one except for the fact that they leak and collapse, as the bulk of the support is a pocket that is now empty.

All my cars (and I have a few) have the solid rubber mounts made by another company other than Anchor. Anchor are fine except they use the same part number (2698) for both the solid and hydraulic MM's. This means that a lot of people have no clue if they fitted hydraulic or solid MM's until the premature failure.

I have two GTS's, one with Porsche MM and the other with my solid rubber MM and there is no difference in the smoothness of the feel of the engine at all.

In fact I would say the solid MM are slightly better. Big dollar difference too, $600 vs. $75.

Roger Tyson - 928s R Us

HYDRAULIC ('83- '95)
The cross section of the hydraulic mount shows the empty void which is normally filled with a mixture of water and antifreeze.

HYDRAULIC (collapsed)
The cross section of the hydraulic mount removed from a car shows the collapsed state which causes the oil pan to sit on the cross member.

SOLID ('78 to '82 inclusive.)
The solid rubber shows the fact that even under the weight of the engine that the solid MM cannot collapse just like the original MM in the older cars.

Please note that these comments are the writer's personal opinions. I take no responsibility nor give any kind of warranty as to the accuracy of the statements included on these pages. The information in Tech Tips is based on the extensive experience of Porsche specialists and owners who drive, service and even race their 928. Although this information is generally considered 'best practice' niether 928 Australia, Landsharkoz or the Webmaster will accept any liability for such information, or, for any use to which it is put. If you have doubts about a specific point, or if you have any questions, you should consult your Porsche specialist or post a question on the Landshark mailing list. - Leonard Zech, Webmaster.