I'm helping get a '97 Jeep TJ with a third party sailcloth soft top out of retirement. This was a top quality lid in its day but it is showing signs of fatigue and brittleness due to its inactivity and sun/weather exposure for a few years. The only visible damage is some tearing at the rear tailgate hooks (a known stress point) and even that is not through all of the layers.
I waxed the (plastic) zippers with beeswax and they are working fine. The 'pieces' that make up the full top were under stress (taut) when I started to unzip them.
I was thinking of applying sheep's lanolin much as one would weatherproof a pair of boots in the hope of restoring something resembling its original suppleness and strength. Is this going to produce restorative properties or just make a slippery mess of disintegrating fabric? It isn't at the 'fall apart' stage yet and I don't want to make it worse. I'm aware that the smell may be strong for a break-in period.
As you may have inferred, I prefer natural products but I am open to commercial alternatives with a proven record.