After 32 years the vertical seal between the two windows was terrible.
In fact, the LHS one was missing and had been replaced with some self-adhesive felt.
Real OEM lists these as Gasket Left & Right (part #12 in this diagram)
Warning – they’re not cheap!
But a good investment for another couple of decades if you're going to hang onto your car.
There’s a lot of misinformation on the interwebs about these gaskets.
No, the rubber seal is not epoxied or glued in place
No, you don’t have to buy the rubber seal as part of the rear window
They can be replaced in under an hour each side - and no need to remove the rear window or rear interior panels as some people think.
Here’s a quick comparison between old & new.
The felt wears away and then the rubber part wears and shrinks.
TO REPLACE:
1. Open the door, gently peel off part of the door seal and remove the 5mm expanding plastic rivet from the door jam gasket
Wind the window down...
There's a small plastic shaft in the rivet that you can either:
i. Push in from the front (and lost forever in the window well)
ii. Push out from the back (awkward, but you can catch the shaft and reuse)
I went with i) as it’s cheap to buy a replacement ( p/n 51161881149)
2. Remove the lower door jam gasket
Gently lift up and out, being careful not to damage the gasket
Have a look where things clip in!
May need to clean the area depending on filth levels.
3. Slide out the old window gasket downwards
Or in my case scrape off the old felt
(3M adhesive remover made quick work of it)
Don’t use anything metal as you’ll scratch the anodised aluminium window support.
4. Slide in the new seal from the base
Pushing from the bottom and guiding from the top.
These seals are expensive, so don’t tear then trying to drag from the top.
Push it home at the base & check the top of the seal sits flush.
5. Refit lower door jam gasket & expanding rivet
Ensuring it’s clipped over the top of the door jam panel and under the rubber interior and exterior weather strip trim.
Done.
