I posted this in the JDM forum, but I thought that the R&C forum may have more direct experience with coilover rebuilds.

So I bought a set of Zeal Function B6 coilovers off of a board member here, they're the ones that VeilsideAP1 owned apparently. Anyway, he said that one or two of the coilovers would need to be rebuilt, so I sent all four of them to Zeal for a rebuild. Zeal told me it would be $100 per corner for a standard rebuild, which would include gas, oil, boots, and seals.

Zeal then checked out the coilovers, said they also need new knobs, two new struts, and two new casings (there is some surface rust on them), and a list of other parts like new pistons, seals, boots, etc., and told me that the total now comes out to around $960 for the rebuild. They have now said that the $100 per corner is only for labor, and that all parts (incl. boots and seals) are extra. Zeal has told me that the coilovers are not in bad condition (a little surface rust, and two of the adjustment knobs don't do anything, which makes them think that the struts are blown), and that this is basically just a standard rebuild, which I thought would be $400. I already have $700 in them, so I don't want to spend an extra $1k just to rebuild them.

Has anyone else had coilovers rebuilt by Zeal, and if so, what was your experience? Also, does anybody have any knowledge of the condition Veilside's coilovers were in when he sold them? I bought them and then shipped them directly to Zeal without really checking them out in depth (my mistake). The two that I looked at appeared to be in fairly good shape though, and I can't imagine $1k for a standard rebuild is really a standard price.

Thoughts/help?

 

Sounds pretty normal to me considering how much needs to be done to get them back to "new"

Most of them time when you get coilovers/shocks rebuilt you're looking at $100-125 per shock for labor + cost of parts. I'd say generally most people that get a full set rebuilt end up paying somewhere around $800-1000.

Unfortunately that is part of the problem you run into taking chances on used suspension.

 

I agree. Sounds like a good deal considering the parts they are replacing, having had a set of JRZs rebuild and revalved I was in just over 1k shipped. Again the price tag on the JRZs is fairly high new, they now work like new, so the 1k was a bargain.

 

And to the OP, note that the time and service to repeat rebuilding on a competition part is much shorter than on a "street" or OEM shock meant to last for 30k miles. Sometimes tuner kids buy competition parts thinking they're "cool" and don't realize the cost of upkeep that is necessary for a performance part. Kind of like buying Hoosiers for your commute to work... if you're not using the item for a performance / competition endeavor, most people are better off buying something for durability.

$700 + $1000 = $1700 which is still a very good price for a quality shock. But if you're not using those adjuster knobs for anything, probably overkill for your application and may not last for street use (which from the previous rust and failure it sounds like that's what happened to the shocks previously).

A lot of guys who have dual-use motorsport cars will swap the fancy shocks back to OEM for the Winter to avoid some of these issues.

 

Ok thanks for the feedback, I have only gone through this process on revalving shocks, not on a standard rebuild, which are apparently about the same price. I may just have them revalve them while they're at it.

The problem with the rust is that these are aluminum coilovers, and the previous owner lived near the beach here in FL. The salt from the saltwater will actually rust cars out pretty quickly if you live close to the beach here. I don't live near the beach, so I don't have to worry about the rust (hopefully).

 

Aluminum corrodes but doesn't rust, no?

 

Exactly, aluminum doesn't rust. And the corrosion isn't corrosion like you normally think of with steel....the corrosion looks like aluminum and actually forms a hard coating around the aluminum which protects it from the corrosion going deeper.

The rust they're talking about must be on steel parts?

 

In response to the original poster, I have had a re-valve of Penskes cost $600 including seals and new shims. I thought that was on the high side; another rebuilder will do it for $100/shock, seals included (shims extra). The former did not send back my old shims; the latter did.

Bare aluminum will immediately react with air to form a thin aluminum oxide coating -- that coating is hard, transparent, uniform, and impermeable. It actually protects the surface from further reactions. Anodizing is a process that forces that reaction further to make the high quality oxide layer even thicker for better protection. Aluminum oxide is also known as sapphire or alumina.

However, certain chemical environments which involve salts or automatic dishwasher detergent will etch away the oxide and start consuming the aluminum, which can lead to pitting and leave a white frosted layer on the surface. That's what is meant when you talk about corrosion of aluminum. The good news is that, unlike with rust, corroded aluminum regrows its protective surface oxide and will not corrode further when you stop exposing it to the chemicals that caused it to corrode. Iron rust on the other hand is porous and brittle and actually promotes additional oxidation by trapping water at the surface of the iron.

 

I highly doubt that every aspect of that coilover is aluminum. Where was the rust? I'd be willing to bed the tophats are aluminum and so is the lower mount but the threaded shock body is probably steel.

 

John, who revalves Penskes for $100 a shock? That's a heck of a deal.