I use 20 / 5wt in my 34. Grip requires 5wt for lower leg and damper duties.

 

Yes, that’s correct. It’s annoying.

 

I also remember putting some Fox Float Fluid in the top of the air spring in the past, but the chart above says 20wt Gold for the air chamber. So apparently the Fox Float Fluid isn't needed anymore, right?

 

You have it correct.

The GRIP2 damper uses the PTFE fluid on the damper side. Regular Fox oil on the air side.

 

The 10wt green spec is old and superceeded. They use 20wt for FIT dampers and air-springs. They use the same damper oil as bath oil in the GRIP fork damper side.

Reality is any oil will work but some work far better than others. Go ahead and use up your 10wt green. The 5wt PTFE isn't that good and the world doesn't need more microplastics. I run Motorex 2.5wt in GRIP dampers and oil bath on damper side.

GRIP damper oil ingestion isn't a big deal, you can run different oils in the bath side of GRIP. Just change the damper oil every year or so.

 

Shameless plug - If you don't want to buy full quarts I'm selling the rest of my fox 5wt and 20 gold in 100ml bottles on eBay. Same ID as on here

 

It'll be interesting to see what they recommend in the future. PTFE, or Teflon if you're DuPont, is PFAS (not microplastics, sorry Dougal) which is being banned everywhere. EU already has regulations, USA is working on implementing them. They'll likely go back to the old oil recommendations.

 

What do you soak the foam rings in on the GRIP damper side?

 

^^^^
Is this a trick question?

 

No it’s not. I heard it both ways. Use Fox Gold for the rings in both sides or use the bath oil for that leg.

 

I just use whatever airside fluid that I'm using for the foam rings. I think Fox Lower Service instructions just use the Fox 20wt or airside fluids.

 

The bath oil eventually gets into the foam rings, correct? So it would make sense to use the same oil for the rings as the bath oil in that leg. It probably doesn't really matter since there isn't much oil in a foam ring, but if you want to be anal it seems like the bath oil and foam ring oil should be the same.

 

I just take 2 plastic cups and fill one with a little 20w and the other with some 5w. Then drop a foam ring in each to soak while I pull the lowers off. After I put the new foam rings in I’ll use my syringe to pull the fluid for each side from the cups and then pour the remaining back into the bottles for next time. Pretty easy and no mess or wasted fluid.

 

I use these.

You can toss out or give away the milk.

 

The objective of the foam rings is to lubricate the stanchions, not supplement the damper bath fluids. Is there a concern of mixing a bit of Fox 20wt with the Fox 5wt damper fluid? Service your suspension on a regular service interval and this should be a minimal concern.

 

If you mix Fox 5wt and 20wt they mix, but if you let them sit they settle. It's not a big drama.

 

GRIP2:
20wt in air-side lower and foam ring. 5wt PTFE in GRIP damper, damper-side lower and foam ring

FIT4:
20wt in air-side lower and foam ring. 5wt PTFE in FIT4 damper. 20wt in damper-side lower and foam ring.

Now whether you use 20wt or 5wt PTFE on the damper-side foam ring in a Grip fork, IMO, isn't going to matter. I've seen it done both ways.

 

The chart is correct. Modern Fox forks use 20wt Gold for all air side baths, soak for the air side foam rings and on top of the air piston. On the damper side, the 5wt Teflon infused oil is used INSIDE the FIT4, GRIP & GRIP2 dampers. Because the FIT4 damper is a totally enclosed system--there is no mixing of bath oil and damper oil--Fox calls for 20wt Gold for lowers/bath oil on a FIT4 fork's damper side as well. NEVER use 20wt Gold inside any damper. It's not damper fluid.

If you have a GRIP or GRIP2 equipped fork, these call for the 5wt Teflon infused oil to be used as BOTH damper fluid AND lowers bath oil. The GRIP dampers are able to purge excess oil into bath area at the top and reingest at the bottom on rebound. Thus, bath oil mixes with the internal damper fluid so both should be the same oil. In addition the volume of the bath oil in a GRIP fork is 40mL (5wt Teflon infused) compared to 10mL(20wt Gold) air side and 15mL (20wt Gold) damper side bath FIT4 forks. Foam rings should be soaked in the same stuff as the bath oil, so for a FIT4 damper fork: 20 wt Gold both sides. GRIP/GRIP2 forks: 20wt Gold AIR side, 5wt Teflon infused damper side foam rings.

In the U.S. the combined price for a quart of 20wt Gold and a quart of 5wt Teflon infused is still cheaper than one quart of 10wt Red for the old dampers. Plus a half pint of FLOAT fluid is a ridiculous price as well. So, the newer Fox forks are less expensive to maintain from a fluid standpoint.

Actually, if you have any older Fox fork with an open bath damper or anything requiring the 10wt Red, it's now the reformulated 10wt Green you require if you want to stick with Fox products. I myself have gone to Redline 10wt (medium) red for my open bath forks. Redline medium kinematics most closely match Fox 10wt red (rebranded Torco) but with a superior Viscosity Index making it more consistent as it heats up. Redline oils can be mixed to achieve different viscosities if u like to play around with that to get a different feel from the fork as well.

A note about FLOAT fluid: it is no longer called for on top of the air side piston. You may note that at least by appearance and feel with human senses, both 20wt Gold and FLOAT fluid have a similar Viscosity and slipperyness (lubricity). They both cling to the sides of the stanchions. Overall it's more economical using the 20wt over the FLOAT fluid. FLOAT fluid is good for refreshing a dropper post between services and people still like to add a few CC's into a rear shock's air can for same reason and timing.