So I have the whole interior torn out, including headliner, to do some upgrades/updates. I fixed my rear sunroof that was leaking heavily by recaulking the bond between outer edge and roof panel. The seal was so far gone it lifted off the roof as if it was never glued down before.

My front sunroof does not leak, but I can't decide if I should break the seal that it does have and create a new one or just leave it be...

Don't fix what's not broken?
Or
Preventive maintenance is the best maintenance?

 

Often that's a roll of the dice. Much depends upon caulk/sealant used and sealing technique.
......

 

Not sure how it was sealed prior, or if it's still factory, but I used a roofing caulk. It smells, but works great!

 

I'd reseal it now so your not revisiting the sunroof (for that reason) later down the road. Having the headliner out is the best time so when it goes back up it's final.

 

I would. Your are so far into the job, I would do it. This summer I am going to pull my headliner and reseal both sunroofs.

This seal is for the glass to the sunroof seal is p/n EEQ500010. Land Rover Parts and Accessories | LandRoverMerriamParts.com (Land Rover Parts and Accessories | LandRoverMerriamParts.com) has them for $45 each.

LR Monthly did a article on repairing drains and resealing sunroofs. I emailed the company that did the repairs for the article about what they used. Here is their response
The sealant we use is WURTH Bond and Seal and their part number is 0890 100 3. The plastic repair is a Kent product called Advanced Plastic Repair APR5 and is part no 85101 34 which is a refill as it comes as part of a kit which includes a syringe to inject and mix the 2 chemicals.

You can get Bond and Seal in the US http://www.shopwurthusa.com/wurthsto...-Ml/p/08901003. You need to buy 3 tubes.

I am looking at using 3M 540 for the sealer. I can get two tubes for $23 shipped. http://multimedia.3m.com/mws/media/5...50-551-560.pdf

I used Devcon Plastic Welder to repair my sunroof drains last year.