Krytox and rear hatch noise

[Tom]

In all the chaos surrounding my recent fuel line leak, I forgot to post this. My rear hatch has rattled and creaked for years, despite new clasps, rubber receivers, adjusting many times, etc. I assumed it was mostly the glass separating from the frame, but I figured no harm trying Krytox to see if it would help. This stuff is incredible. I put it on the weather stripping and paint all around the full length of the hatch opening and all around the pins/clasp area -- anything that touches something else when the hatch closes. The results were just amazing. Zero noise from the hatch, despite the glass delaminating. Can't recommend this stuff enough.

Krytox comes in a little tiny tube, but it goes a very long way since you need very little for it to work -- think greasy fingers leaving a smudge. It's designed to work on virtually all car surfaces too without staining or damaging --paint, rubber, leather, vinyl, etc. I got my little tube from the tech at my Porsche dealer (when chasing rattles on my 991) but you can get it on Amazon, etc. My dealer used GPL 206 in a gel, but there quite a few types to choose from. This stuff is worth its weight in gold for those who hate squeaks, creaks, and rattles. That is all.

https://www.krytox.com/en/applications/nvh

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[ROB III]

Tom, did you reach out to Krytox as I see they have different numbers for their grease, 203, 204, 205, 206, 207. I'm definitely getting one (or more) of them as my hatch creaks are very irritating. (Strange though the hatch was removed for the repaint and when it initially was returned, the creaks were gone, but eventually returned.)
One of the roles I had when at Nissan was evaluating and prepping journalist cars and NVH is something I used to focus on along with dynamic characteristics, so I'm always trying to track down and kill any squeak, creak, rattle, whistle, whatever.
I was concerned about silicone content due to painting issues, but their white paper points out negatives of silicone so I'm thinking there is none in their grease.
Thanks for your post!

[ROB III]

Follow up...I have sent an email to Chemours to see if they have an application chart for the different PFPE grease they offer to see if we might find other applications for their various products.

[Tom]

Check them out online too. They publish a ton of literature about it, broken into industries and applications (with lots of application charts)....

https://www.krytox.com/en/industries/automotive

[Alex89]

Tom I'm curious why you would add grease instead of an adhesive? Seems you are adding more work for when you need to reseal the glass later.

My hatch was just starting to delaminate near the hinges. I could have ignored it but the rattles and creaks were annoying. I've read about issues caused by silicone, but I found a tube of Permatex Polyurethane sealant in the rtv aisle. Without doing any hatch disassembly, I trimmed away any old hatch adhesive I could access, cleaned around the edges of the glass with isopropyl alcohol and a toothbrush, then carefully laid a bead of polyurethane around the inside of the hatch, filling the gap between the frame and hatch glass. In the area where it was delaminating I was able to push up on the glass a bit and get the adhesive deep into the gap. I then just closed the hatch and let the adhesive dry without clamping or adding any external forces. That was 2 years ago now and no signs of new delamination, and the rattles and creaks are gone. But importantly if I ever need to seperate the hatch frame and glass to reseal it "properly" I don't see the additional polyurethane adding any complications.

[Tom]

Tom I'm curious why you would add grease instead of an adhesive? Seems you are adding more work for when you need to reseal the glass later.

My hatch was just starting to delaminate near the hinges. I could have ignored it but the rattles and creaks were annoying. I've read about issues caused by silicone, but I found a tube of Permatex Polyurethane sealant in the rtv aisle. Without doing any hatch disassembly, I trimmed away any old hatch adhesive I could access, cleaned around the edges of the glass with isopropyl alcohol and a toothbrush, then carefully laid a bead of polyurethane around the inside of the hatch, filling the gap between the frame and hatch glass. In the area where it was delaminating I was able to push up on the glass a bit and get the adhesive deep into the gap. I then just closed the hatch and let the adhesive dry without clamping or adding any external forces. That was 2 years ago now and no signs of new delamination, and the rattles and creaks are gone. But importantly if I ever need to seperate the hatch frame and glass to reseal it "properly" I don't see the additional polyurethane adding any complications.

Sorry I probably wasn't too clear. I actually had a windshield place do the same thing to my hatch a few years ago. I'm not entirely sure how well it's holding up, but good enough it seems. My noises were coming from where the hatch touches the weather-stripping and body all around the big opening, and the pins. I adjusted things until I was blue in the fact (pins, clasps and hinges) but couldn't get it to go away. I blame the replacement weather-stripping most likely. Anyway, that's what I put the Kryton on -- the weather stripping and every place where the hatch makes contact with the car (including pins). It made a massive difference -- from creaking old farm vehicle to reasonably rattle/squeak-free car inside. As previously reported, I also used the Krytox on the sunroof, with similar (awesome) results!

[cda951]

An interesting data point: when I first bought my 951 ~ 15 years ago it had some minor hatch rattles and creaks, nothing egregious, not as bad as some of my customer 944 hatches. I started doing a lot of track days, so within a couple of years I installed an Autopower 4-point roll bar. No more rattles, creaks, of any kind. Not a peep, and the hatch has always opened and closed easily since replacing the hatch pin inserts.

I am not suggesting that everyone install a roll bar, but merely pointing out that in addition to hatch glass/frame issues, we are fighting chassis flex, especially with that gaping hole in the rear of the body shell.

[Tom]

An interesting data point: when I first bought my 951 ~ 15 years ago it had some minor hatch rattles and creaks, nothing egregious, not as bad as some of my customer 944 hatches. I started doing a lot of track days, so within a couple of years I installed an Autopower 4-point roll bar. No more rattles, creaks, of any kind. Not a peep, and the hatch has always opened and closed easily since replacing the hatch pin inserts.

I am not suggesting that everyone install a roll bar, but merely pointing out that in addition to hatch glass/frame issues, we are fighting chassis flex, especially with that gaping hole in the rear of the body shell.

I have the Redline bolt-in roll bar -- it bolts to where the rear seat belts were. Not sure it creates as much rigidity as the Autopower version (which bolts to the floor board?). In any even, my hatch made lots of noise despite my roll bar. I honestly think it had something to do with the new/replacement weather stripping rubber, since treating that with the Krytox worked miracles...

[cda951]

An interesting data point: when I first bought my 951 ~ 15 years ago it had some minor hatch rattles and creaks, nothing egregious, not as bad as some of my customer 944 hatches. I started doing a lot of track days, so within a couple of years I installed an Autopower 4-point roll bar. No more rattles, creaks, of any kind. Not a peep, and the hatch has always opened and closed easily since replacing the hatch pin inserts.

I am not suggesting that everyone install a roll bar, but merely pointing out that in addition to hatch glass/frame issues, we are fighting chassis flex, especially with that gaping hole in the rear of the body shell.

I have the Redline bolt-in roll bar -- it bolts to where the rear seat belts were. Not sure it creates as much rigidity as the Autopower version (which bolts to the floor board?). In any even, my hatch made lots of noise despite my roll bar. I honestly think it had something to do with the new/replacement weather stripping rubber, since treating that with the Krytox worked miracles...

Yes, that is good to hear about the Krytox, will probably help my life at work a lot

I remember trying to get one of those Redline roll bars way back when, but couldn't get my hands on one. The forward feet of Autopower bolt to the floor pan at the rear seat footwells, and the rear feet bolt to the wheel housings. So I would agree that this aids torsional rigidity of the rear of the body shell, which helps with the hatch moving around. The Redline roll bar is anchored at four very strong points of the chassis, but likely does not help with torsional rigidity as much---I am certainly no engineer, but one does not have to be to conclude such a thing

[Tom]

I'm no engineer either, but yours is almost surely more rigid. The redline one essentially mounts to the side walls of the car, so can't possibily lock it in the way yours does.

I learned about Krytox from a Porsche dealer mechanic. Great guy and great tech...he told me they use that stuff extensively on Panorama's when people complain of squeaks and creaks, since a lot of those drivers are going for the luxury car experience really. He actually said what you just said -- makes their lives way easier then spending hours trying to pinpoint noises.