You are hereForums / By Discipline / Mountain (off road) / MTB Gear / Fox suspension oil selection

Fox suspension oil selection

M.Jackson's picture

By M.Jackson - Posted on 29 January 2015

NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.

Hi guys, I am after a bit of advice.
I need to replace the seals and dust wipers on my 2008 fox talas 32 forks, I called my LBS which have a seal kit to fit, however it is only compatible with the new fox 20wt gold oil. Fox says this oil should never be used with open bath damped forks (which mine are), however the mechanic says his forks are open bath and he runs this oil.

Can anyone weigh in on their opinion/experience, do i order in the older seal kits and use 10wt oil or put in the new seal kit and 20wt oil and ignore fox.

Cheers for the help

lgt's picture

After last years CtoC i replaced my fox f32 fork seals and i run Silkolene 10 weight racing suspension fluid it is a motor cycle fork oil synthetic and have had no problems. my forks are open bath also.Fox say to use 10 weight oil and if you use a 20 weight oil it will make the forks less responsive to small bumps and make the fork action a lot stiffer.

Tom M's picture

It's my understanding that the new gold seals can be used with the older red green oils. It's the old seals that can't be used with gold oil.

I've also read that gold oil is just motor oil and not for open bath setups.

M.Jackson's picture

Thanks for the advice guys, I have ordered in a set of the old seals and plan to put non fox 10wt oil in (although tempted to use the 15wt that i already have from my motorbike). Does anyone have some 10wt which they wouldn't mind sharing some of, I need 40ml, so it seems a waste to buy a Liter of it.

hathill's picture

You'll need more than 40ml's for an open bath damper - Fox RL 100's need 155ml's for the damper side. Your Talas will need more I would say. Go here to check. I just use mobil 1 0w - 30 synthetic for the spring side lube and Castrol 140W synthetic for the actual air spring.

M.Jackson's picture

Your right, sorry that is where I got my info from, just read the wrong line (for the 2010 instead of 2009). I need 150 damper side and 20 spring side.

M.Jackson's picture

How did you come to the combination of mobil 1 0w - 30 synthetic and Castrol 140W synthetic?

hathill's picture

0w - 30 is for the lowers, separate to the 140w for the air spring.

M.Jackson's picture

I think I worded my response poorly. How did you decide that the damper side needs 0w30 and that the air spring needs 140w? at normal running conditions your damper side must be much less viscous then the 10W recommended and there for give less damping, I have no idea what a change in the air spring side would do to behavior.

It is nice gaining a little more understanding on suspension. I have never really come to grips with pinpointing a suspension set up, I found a sag that felt right (which seems to be in the ball park of what most other people run) and then had a bit of a play with the rebound until it felt pretty good and then never really looked at it too closely again.

hathill's picture

No, I think I mucked up my response when I referred to lowers. I just mean use the cheap stuff in the lower on the spring side. I still use fox 10 wt in the damper side. The float fluid is essentially synthetic year oil so that's why I use the 140 in the air spring. Gear oil is also my favourite chain lube but that's another story Smiling

delicious's picture

I'm a very big fan of using exactly what the manufacturer recommends for their particular product. I've been using Fox suspension for a long time and have learnt all about servicing and maintenance. I have the correct tools and a proper work area. My Fox items are becoming a bit old these days yet, they are in great condition through proper care. They are always reliable.
So, do as they say as they know best. Have a schedule and stick to it. One who invests in a high end bike, or buys suspension separately, ought to look after it properly. Those who ride a lot need to service their suspension a lot.
It enrages me when I hear people neglecting their suspension on the logic of expense, and that they will simply move the bike on in whatever time frame. Thus, some poor bastard that buys it second hand will have a wrecked item! This is an appalling attitude.
Look after your suspension people. It pays dividends in ride quality and longevity. If you are unable to it yourself, for whatever reason, then outsource it. Just get it done.

M.Jackson's picture

An update to the saga, Fox no longer make green oil or the seal kits which go with it. The LBS (in consultation with fox)now say to install the new seals and gold oil and that it will just require a different damper setting but will still be work fine.

Mamil's picture

That's an interesting development, as it goes against what Fox explicitly state on their web site here -

"The new 20wt. Gold Bath Oil may be used with FIT and O/C damper cartridges but should NEVER (their capitals - not mine) be used in open bath fork dampers."

And other shop service centres I've talked to have been told by fox to use the Red in O/B dampers & lowers once they run out of green.

I'm just glad I stocked up on enough Fox Green to see my O/B forks through a couple of years of servicing before I have to worry about their confusion on this issue!

PS: If anyone's interested, you can still buy the Green from here -

M.Jackson's picture

And the second LBS I called (one who do a reasonable amount of suspension surviving, particularly for those in the western suburbs) say that they are still using the green oil but changed a long time ago to the new seals even though fox say the new seals should only be used with gold oil.

The option which is most likely to go into my forks unless more is learned by the weekend is the new seals with non fox suspension fluid. I have some 15wt castol fluid at home, which has a viscosity very close to the fox 10wt, 46.5cSt vs 47cSt @40 degrees Celsius.

Mamil's picture

Are you sure Fox say the new seals shouldn't be used with Green? Where do they say this?

I've only seen them say the old 32mm seals shouldn't be used with the new Gold, and my understanding is this is because unlike Red & Green which were specifically manufactured to Fox specs, the new Gold is just re-badged motor oil, and has some additives not compatible with the old 32mm SKF seals, which could cause delamination.

M.Jackson's picture

When in doubt email fox.
The response for fox reads as follows:
"You would still want to use the current 32mm dust wiper seals, however you would definitely not want to use the gold oil as this is not a damping fluid. Depending on what oil your local bike shop has in stock you can use either the green 10wt. or red 10wt. oil. The green oil has been discontinued so your shop may not have this anymore and the red oil has taken its place in older open bath forks."

My confusion about thinking that the new seals could not be used with green oil came from 2 places firstly TBE's website which reads "These seals can be used in all 32 millimeter stanchion forks, but 20 weight oil must be used as well." which I took as only the 20wt oil can be used with them
The second place was that on the packaging of them the have "for gold oil" or something very similar, which seemed to back up what was said on TBE's site.

Thanks for all the help and I hope this saves someone else doing all the research I had to.

Mamil's picture

Yeah, that sounds more like it, and is in line with what I've been told by shops who service Fox. Still think the best solution if you have an old O/B fork is to stock up on a couple of litres of Green while you can still get it. Red is good for the damper, but less than ideal for the bushings.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Best Mountain Bike