Shock absorber boots!!!!

[Pete Attryde]

Morning,

On the way home last night my near-side rear shock absorber decided it didn't much like it's contents and spat it all over the rear of the Discovery. Investigating the cause when I got home I found that the piston rod had corroded inside the shock boot causing the seal to fail. This was partly caused by the fact that I took the 2" lift springs off and re-fitted standard height ones, leading to the shock running on the damaged part of the rod. This is the second failure of a shock in this position in 9 months, the first one failed in a similar manor but caused by rocks bouncing off the rod (I didn't have the boots fitted) and damaging the surface. The shocks were from different manufactures (both reasonable but not the most expensive) so I don't think it is a design issue, however I am now at a loss as to how to stop this happening.

What are others running/ how do you stop this happening.

[v8bertha]

I run shocks with rigid boots that are not sealed.

The trouble with the Pro-comp concertina type boots is that you cable tie them on at either end and they become a moisture trap, condensating on the shaft

Rigid boots on the other hand such as those on Delphis or Old Man Emu shocks are open at the bottom end allowing moisture to escape easily. And you have the added bonus of the rigidity that deflects rocks, sand and other debris that gets thrown up from the tyres. After several thousand miles on gravel roads its amazing to see the damage that can be caused to the shocks. Ours had effectively been shot blasted by the grit

Dan B)

[chadler]

The boots on/off angle has been debated here before: short term protection from rocks and gravel but condensation causing corrosion instead.

I've got procomp ES9000s on the 90, and whilst their damping is superb, they're just too susceptible to damage; all the pistons quickly showing signs of corrosion resulting in seal failure. Of course, it might be that with fixed metal-shield dampers the corrosion is there too, but not seeing it leaves you in blissful ignorance?

[bishbosh]

I have had rubber boots on my Bilsteins for over 5 years and the shafts are fine.

The boots do have drain holes at the lower end though.

I'd agree with Dan - solid "boots" are the best way.

[Pete Attryde]

Cheers folks,

The boots on these shocks also have drain holes at the bottom but obviously not in the right place. I have spoken to the supplier of the shocks (David @ LLama4x4) and they are sending me a replacement under the warrenty which is good, however I have also paid out for a set of old man emu shocks from Gwyn Lewis (Nice man to deal with on the phone.)

Interestingly from chatting to David it seems as if he is in the process of designing a better system for use with the rough country shocks.

[Mark90]

I'd agree with Dan - solid "boots" are the best way.

Yep.

I've had corrosion problems on pro comps both with and without the rubber boots fitted, maybe the quality of the shaft has something to do with it too.

[Scotian]

I'd be intersted in hearing what he comes up with for the rough country shocks. Thats what I am using and the boots are begining to split at the top. Also they squeek like 4 mice having a party whole time when trundling along undulating road. Really annoys me.

[clbarclay]

One thing I dislice about the plastic consatina boots is they prevent full compression of the damper as the internal diameter is too small.

On my first RRC (procomp es9000) the fronts are concealed within the standard turret so did fit them and fitted them to the rear but only fixed at the top, so far haven't had any problems with it and it doesn't reach full compression anyway so.

On the second RRC I used the 11" rough countries and softer springs and found the boots were acting as a bumpstop on full travel so duely removed them. Not sure how many miles they have done know, but the shafts are starting to show the odd sign of stone scrapes and chips in the chrome so have refitted them but trimmed the bottom half off the boots. The boots are just long enough now to cover the shaft at standard ride height to prevent scratches and chips whilst on the road, very open at the bottom so water and dirt falls out and allows as much compression as possible. I would still by far prefer to have a solid sleve/boot like standard dampers, but at the time I couldn't afford OME.

[denviks]

im with chris on that one. on my discovery i had procomp es9000's fitted allround. i had the rubber boots fitted at the top only with a cable tie. this alows the muck and water drain out aswell as moisture but still gives the protection needed.

in 3 years of heavy offroading i never once had a problem.

[Pete Attryde]

I actually think that a factor in the corrosion on mine is that it has hardly been off-road since I fitted the shocks, this has ment that the shocks have only been using a very small amount of their travel most of the time and the rest of the rod has not been wiped clean by the seals on a regular basis. I will just have to get the thing muddy more often to cycle the shocks to prevent corrosion .

[nicks90]

i've had my procomps on the 90 for almost 5 years now, and the pistons are only just showing signs of rust towards the top 1/2" of the shaft,

no shock boots fitted! It does get offroaded once a month, but when i do the clean down and regrease the props etc, i wipe a very thin smear of vaseline on the shafts. No idea if this is preventing any corrosion occurring whilst its used as a road car during the rest of the month, but i do think the vaseline helps and prevents road grit sticking to the shafts - meaning when i do compress them offroad, the seals dont have as much of a job scraping the grit off and knackering them.

Also the shock bodies are almost completely grit blasted on the leading edges, with no white paint left! But the shafts still look good.