Bilstein shocks warning.

[generubin]

Hey, I want to tell you, as nice as the ride is with the Bilstein 5100, don't buy them. I blew out a second shock on a washboard road. Only 6 months old, two bad ones. Speaking to the two tech guys at Bilstein, they both agreed their shocks can't handle washboard. When I told the techs that 30+ years of using ProComp or Rancho I never had a failure they said "Well, of course not, only mono-tube designs overheat to the point of failure". All Bilstein models are mono-tube, they told me no model Bilstein would be able to handle washboard heat build-up. They told me that maybe their 5160 might do the trick with its extra reservoir but they agreed at $200 per shock, better not to take the chance. They even read to me a paragraph from their documents that states, "for highway or light off road only". Without saying the actual words, if I didn;t want to invest heavily and experiment, they were recommending I go back to twin tubes. Incredible!

So, if you're doing the sorts of desert off-road, washboard roads, that I do, stick with Rancho or Procomp (and not the mono-tube designs). I ordered a new set of Procomp 9000. I'll put my remaining rear Bilsteins on ebay. Bilstein 5100 were like $360 a set, the Procomps on sale at $160 a set!

Gene

 

[ski3pin]

Hey, I want to tell you, as nice as the ride is with the Bilstein 5100, don't buy them. I blew out a second shock on a washboard road. Only 6 months old, two bad ones. Speaking to the two tech guys at Bilstein, they both agreed their shocks can't handle washboard. When I told the techs that 30+ years of using ProComp or Rancho I never had a failure they said "Well, of course not, only mono-tube designs overheat to the point of failure". All Bilstein models are mono-tube, they told me no model Bilstein would be able to handle washboard heat build-up. They told me that maybe their 5160 might do the trick with its extra reservoir but they agreed at $200 per shock, better not to take the chance. They even read to me a paragraph from their documents that states, "for highway or light off road only". Without saying the actual words, they were recommending I go back to Rancho or Procomp. Incredible!

So, if you're doing the sorts of desert off-road, washboard roads, that I do, stick with Rancho or Procomp (and not the mono-tube designs). I ordered a new set of Procomp 9000. I'll put my remaining rear Bilsteins on ebay. Bilstein 5100 were like $360 a set, the Procomps on sale at $160 a set!

Gene


Gene, incredible story. I hope these techs are able to keep their jobs. Where is there not washboard?

 

[SunMan]

Interesting story Gene, I always figured I would go with Bilsteins the next time around beacuase of all I have heard about them. I have always used Ranchos and never had a problem, until I blew a RS 9000 out during a two week Baja trip a couple of years ago. They were less than a year old. Fortunately I found out something I didn't know about them....they are guaranteed for life and Ruben at Ventura 4x4 replaced it for free. Maybe I'll reconsider now. Do Bilsteins not have a similar guarantee??? Sorry to hear about you misfortune.

 

[craig333]

Ack, now you tell me. Thats incredible. I think I'll have a week off for thanksgiving, was thinking of trying the washboard in DV/Saline. Well I still will, I"ll just be a bit more paranoid about it. Thanks

 

[generubin]

@ ski3pin: I was very impressed by the techs. They stand by their product, they just state that off road is not what the yellow/blue, 5100 nor 5160 are designed for. The only way to get an "off road" Bilstein is from their custom shop at hundreds per shock. At first I was furious with Bilstein but now I respect them for their honesty. It is the 4wd shops that promote these as off road shocks.

@ Sunni, Lifetime warranty on the Bilstein as well. But I'd rather not swap out the shocks after every trip down washboard, not to mention spend the trip home with no shocks. It is the front shocks that burn up as the front is coil sprung on my Dodge 2500. The rears are fine as leaf springs do much of the help dampening vertical movement. The friction between leafs works as a dampener which is why those smart men who designed the stagecoaches made them as they are. When a leaf compresses there is horizontal friction between leafs to slow the movement. A torsion bar or coil sprung suspension is like a bouncing Superball without a shock. A leaf suspension drives fine with no shock at all! Where as the rubber boots melted right off the fronts, the rear boots (leaf sprung) have not melted at all. I will send these two fronts in for replacement and sell the new fronts and used rears on ebay. I generally swap out my Ranchos or Procomps every 50K just for fun.

@Craig333, Normally I do Saline washboard at 40 to 50 mph. This last time, yesterday, I was in no hurry. Going only 25 mph I wasted those two fronts.

See this link for important Saline Pass washout condition (the pictures are not 3D so they don't nearly do justice to the conditions). Infinitely worse conditions than I have seen in my 29 years of Saline trips: http://forum.salinepreservation.org/post/South-Pass-100712-6040807?trail=15 You need to be able to crawl at 2 to 3 mph with full torque to go up the Saline South Pass. I have a locker in the rear, without it I'd still be there. You have very steep uphills over boulder fields of which some boulders that you cannot go around, many so large you can not move them. So, if you're in a 1/2 ton or a rice burner your gears may be too high. Going in the South Pass (meaning downhill) any truck with good clearance will make it. You'll need good articulation so if you are running airbags this may limit your control.

 

[SunMan]

But I'd rather not swap out the shocks after every trip down washboard, not to mention spend the trip home with no shocks.

I figured as much but was curious about the warranty. So far so good on the Ranchos since the replacement, plenty of Baja and DV washboards since then, fingers crossed. Glad you had a good trip otherwise.

 

[SLO_F-250]

Guys, this is very interesting. I had the exact opposite experience. I built a full size chevy into a prerunner in college. Lets say I went through LOTS of shocks. Blew up pro-comp's 2 sets of ranchos with dual's each side up front, and finally went to dual bilstein 5150's in the front. The were great shocks. My front end cycled 14" of travel at the time and the 5150's worked GREAT! When I finally saved up for 2.5" diameter Racerunners in each corner I took the 5150's and threw them on my F-250 and are still working well after 7 years.

 

[ntsqd]

I run Bilstein's & Fox's and will NEVER go back to a twin-tube type of damper. Twin-tubes never fail like this because they over-heat and fade away before they get the chance to hurt themselves. Before you give up on a superior design you might try employing two, purpose valved dampers per wheel.

The issue is the heavy axles, particularly the front being coil sprung. If you are blowing them up you're either going too fast for the dampers that you have, or you don't have enough damper to start with, or both. Of course Bilstein would put such a caveat in their literature, they'd be replacing abused dampers willy-nilly if they didn't.
Friends with Early Broncos (lighter front axle under coil springs) used at speed on week-long desert exploration/camp trips use 2.5" body, 5/8" shaft Fox's to keep those suspensions under control. They're not going pre-run or race speeds, but they're not lolly-gagging around either. If it takes that much damper to control a lighter axle then trying to go that fast in a full size with a single 51XX series damper per tire is asking for a failure. Just trying to keep their dust in sight is probably still asking for a failure.

I put 5165's on our '96 CTD. If they don't perform or fail I'll step up to a set of remote reservoir 7100's and use the 5165's valve stacks as the jumping-off point for the damper tune.

 

[generubin]

I run Bilstein's & Fox's and will NEVER go back to a twin-tube type of damper. Twin-tubes never fail like this because they over-heat and fade away before they get the chance to hurt themselves. Before you give up on a superior design you might try employing two, purpose valved dampers per wheel.

The issue is the heavy axles, particularly the front being coil sprung. If you are blowing them up you're either going too fast for the dampers that you have, or you don't have enough damper to start with, or both. Of course Bilstein would put such a caveat in their literature, they'd be replacing abused dampers willy-nilly if they didn't.
Friends with Early Broncos (lighter front axle under coil springs) used at speed on week-long desert exploration/camp trips use 2.5" body, 5/8" shaft Fox's to keep those suspensions under control. They're not going pre-run or race speeds, but they're not lolly-gagging around either. If it takes that much damper to control a lighter axle then trying to go that fast in a full size with a single 51XX series damper per tire is asking for a failure. Just trying to keep their dust in sight is probably still asking for a failure.

I put 5165's on our '96 CTD. If they don't perform or fail I'll step up to a set of remote reservoir 7100's and use the 5165's valve stacks as the jumping-off point for the damper tune.


Hello ntsqd, you have completely made my point of this thread. Don't go out and buy a set of 5100's which are so heavily promoted by 4wd shops and expect them to work on washboard roads. It was the techs at Bilstein who noted to me that their lit states, "for light off road use only". Yet due to heavy sales promotion by retailers, these are sold in mass to off roaders. Even the NPS was sold many sets only to have to replace them with twin tubes. There's performance and there's reliability. I always choose reliability, might save a life one day.

Yes, I totally get it, I am aware that the twin tube design dampening fades and decreases under heat but I've spent 40 years on the worst washboard imaginable. I've done thousands of miles of the African Sahara, all over Baja and mainland Mexico, all over the USA and Canadian arctic, hundreds of thousands of miles, with never a single shock failure, I always got from point A to point B without oil spraying all over my truck. My Bilsteins blew at 25 mph with less than 1,000 miles on them. Sorry, I am not going to sink myself even deeper into the same design.

As an ex professional mechanic, I used to be all about mods and race parts. In my distant travels I have learned that most failures in the field result from straying from original design and especially overloading above payload.

I understand your shocks with much experimentation and many hundreds of dollars spent won't fade like mine will. I've made it to 56 years old using inexpensive, 100% reliable twin tube design. I think I can go another 20 years till I fall over dead. I suppose if trucks was my #1 hobby, I'd maybe sink that kind of money into shocks. I have too much on my plate already; rental units, fiddles, mandolins, son's college education, girlfriend's health issues, travel, and spare time as my hobbies. Damn! I wish life was simple again!

 

[generubin]

Though the techs read to me on the phone that the 5100 is "not approved for other than light off-road use", I can not find that info anywhere on the Bilstein site. Even the owner's manual for the shock does not state this.

In looking how to send these two blown shocks in for "lifetime warranty" replacement, the warranty webpage states there is no warranty for shocks used off road. Hmm....WTF!

 

[ntsqd]

I've hammered on two sets of 5100's under the front of my '84 Yota Mini while chasing desert race cars. I say two sets because I was noticing that the front end was behaving slightly odd and thought that it might be due to the shocks so I replaced them (went from the yellow bodies to the plated bodies). That wasn't it, the steering trunnion bearings had become a victim of that hammering. Never noticed either set to fade or leak. Though-out most of that hammering the 7100's have been under the rear and show no signs of needing anything.

Some Bilsteins will perpetually have a "damp" shaft though I'm guessing yours was more than that. I have noticed that Bilstein's do have a break-in period. At a 1000 miles I'd have thought that you'd be past that by then, but perhaps not. As with anything, the higher the performance, the more narrow minded and potentially finicky they become.

Don't have to buy new 7100's, they come up for sale fairly regularly on rdc. Anyone with dirt bike shock experience will find them simple to work on and rebuild. Adding a tank valve to the 5100's would make them easily rebuilt as well. They really aren't much different from the 7100 series, except for possibly the valving inside them.

 

[Bat]

I have a hard time reading this about Bilstein shocks and that a tech guy would say it can't handle washboard road and for light duty. The whole idea how they are built is to stop fade and heat build and that is why they are just a great shock. I have been a lifetime Bilstein buyer and have never blown a shock which was matched to my truck and weight. This is of course my own opinion your experience has been different then mine and sorry to hear about the problems.

 

[ntsqd]

This has been bugging me for a bit. Gene, where did the dampers fail? The rod guide & seal or around the outer edge of that insert? Prior to the section of road/trail where they did fail was it high(er) speed wash-board or similar?

I've seen the rod guide & seal fail from hard usage, but to do that usually means that they're on a desert race machine and have seen many race miles. To fail within 1000 miles on a less stridently driven vehicle seems unusual to me, off road use or not. And there's no way that they should have failed purely from a slow speed, technical section. My intuition says that they finally let go in the slow tech section, but that the actual failure happened before then.

The buckling strength of 14mm shaft used in the 5100/6100/7100 series limits the valving to slightly more than their usual coil spring application valving of 360/80 (maybe 400/100?). For hard use with coil springs that's usually not enough damping. For casual use it's more than fine. For hard use a single damper with a larger shaft OD and body OD (for more oil volume) is called for. A more moderate, but slightly less capable solution is dual dampers that are valved specifically for dual per tire use. Bilstein does offer such valving in the 5100 series, but you have to order it specifically.

I did not intend to imply that twin-tube dampers fade to protect themselves, and then once cooled off resume their damping duties un-phased. That isn't how it works. Fade them badly enough just once and they will never come back to full capability and they may not come back at all.

 

[generubin]

This has been bugging me for a bit. Gene, where did the dampers fail? The rod guide & seal or around the outer edge of that insert? Prior to the section of road/trail where they did fail was it high(er) speed wash-board or similar?

I've seen the rod guide & seal fail from hard usage, but to do that usually means that they're on a desert race machine and have seen many race miles. To fail within 1000 miles on a less stridently driven vehicle seems unusual to me, off road use or not. And there's no way that they should have failed purely from a slow speed, technical section. My intuition says that they finally let go in the slow tech section, but that the actual failure happened before then.

The buckling strength of 14mm shaft used in the 5100/6100/7100 series limits the valving to slightly more than their usual coil spring application valving of 360/80 (maybe 400/100?). For hard use with coil springs that's usually not enough damping. For casual use it's more than fine. For hard use a single damper with a larger shaft OD and body OD (for more oil volume) is called for. A more moderate, but slightly less capable solution is dual dampers that are valved specifically for dual per tire use. Bilstein does offer such valving in the 5100 series, but you have to order it specifically.

I did not intend to imply that twin-tube dampers fade to protect themselves, and then once cooled off resume their damping duties un-phased. That isn't how it works. Fade them badly enough just once and they will never come back to full capability and they may not come back at all.



The very first front 5100 that failed on me had less than 500 miles on it. It failed on its first stretch of south Saline Valley Pass. I was maybe 15 miles into medium grade washboard at around 25 mph when all of sudden I smelled oil and smoke. I'd say the full amount of oil that the shock holds suddenly blew out all over the front axle and hit the motor causing smoke. It looked like easily 1/2 quart of oil. The wonderful folks at Geno's Garage (I highly recommend Geno's, always excellent service) sent me an advance replacement and a return shipping tag for the defect. The other front shock I noticed the boot had melted to the housing but no oil was leaking. My first thought was maybe the wrong dimension shock was sold to me, that the shock bottomed before the suspension stops, but I then double checked this with Geno's and Bilstein, I triple checked it by measuring the suspension travel of my truck and making sure the shocks had greater travel which they did. After the replacement, I did a Baja trip that was more sandy, not very washboarded roads and the shocks were fine other than the new one melting the boot off.

My more recent incident last week, I had already traveled into Saline via the mellow North Pass. We were headed out on our way home via the South Pass which has heavier washboard. Long before anything technical, while never going faster than 25 mph, only 20 miles from the Springs, again, a sudden smell and smoke of oil only to find a soaked axle and engine compartment. I'm guessing the failure is at the seal where the shaft enters the body resulting in full and sudden loss of oil.

2 days ago I looked over the Bilstein website and noticed they advertise the 5100 as on/off road shocks. I was looking for the wording that the Bilstein warranty person had just read to me over the phone "for on road and light off road only", but I could not find these words on the website. I went to the warranty link to get an address to send my two front shocks to. When reading the warranty info it says for most every model they make: "no warranty if used off-road". So, they sell it as "off road" but do not warranty as "off road". Further, for the 5100 model, the Bilstein site says they should be returned to the retailer. I called my retailer just to inform them of the situation, I already figured I'd get no warranty as I was honest about leaving the pavement with my 5100's. Scott, at Geno's Garage, insisted on returning my purchase price 100%. I told him I really wasn't expecting any return at all but he insisted on making a full return. Again, Geno's Garage, I highly recommend.

The rear 5100's have been fine. The boots have not even melted. This is likely due to the natural damping effect of the leaf springs (which is why buggies and stage coached used them). Front coil or torsion bar suspensions bounce like rubber balls, the only dampening being the shocks.

Your comments of twin tubes not coming back after fading. I have never found that to be the case. I get a good 50k miles out of the Ranchos and Procomps I have used.

The Sahara desert is the size of the USA with not a single stretch of pavement more than a few miles long. The Trans Saharan Hwy is occasionally pot holed pavement, but mostly seriously world class washboard. The transit trucks have tires 6 feet tall so you can imagine the size of washboard created. We are talking washboard like driving over those concrete stops used in parking lots. I've driven over 6,000 miles of this sort of road from 10 to 20 mph, any faster was impossible. A hundred mile day might take 10 hours. Between some villages in Algeria we had 700 miles, a weeks worth before the next town. I was using a Mitsubishi L300 4x4 van which I prepped in the auto shop I was a mechanic in, in Switzerland. I had twin tube shocks from which manufacturer, I forget but likely Monroe (choices in Switzerland are limited). Never a failure and they were still fine once we returned to Switzerland. Of note, the L300 uses leafs in the rear and torsion bars up front. I was heavily equipped with spares (shocks, wheel bearings, 4 spare tires, belts, fuel pump, CV joints etc.) for the Sahara trip but I had no failures whatsoever. I did spend plenty of time helping to do field repairs of Vanagons, Peugots, Land Rovers and Unimogs (don't even get me started on a Unimog rant!).

I'm not upset at all with Bilstein. The techs were attempting to help out as much as possible. Washboard roads are tough on equipment. You try a few things and stick with what works. Bilsteins don't hold up for me, the others do. Same with trucks. I had Isuzu Troopers with doors splitting, Toyota pickups with cracking chassis, Nissan Frontiers with transfer case gears too high, etc, etc. Best truck for me so far has been my Dodge Cummins with a manual trans. I never would use an automatic in the wilds. An auto trans is the single most complicated, #1 most likely component to fail completely whereas a manual trans is near impossible to fail without thousands of miles of clear warning. These days, the only full size truck with a manual is Dodge. Over 600 mile range on a tank of fuel. I have 60,000 very hard miles on my 2006 with zero problem. So far, I'm pleased. MPG is 18 to 19 with ATC, I could use 25 to 30 mpg, couldn't we all?

 

[Bat]

How are the boots on the shocks melting I am not understanding.

 

[generubin]

How are the boots on the shocks melting I am not understanding.


When the shocks overheat, the boots melt off.

 

[ntsqd]

However it is that you're doing it, to get them hot enough to melt the boots you're pushing the 5100's beyond their envelope. Odds are reasonable that dampers with a reservoir might be enough to work and live (like the 5165's), but I suspect that you would really need to move to more oil volume than just what a reservoir provides. Experience has shown that a single 2.5" bodied damper is better than dual 2.0" bodied dampers regardless of any oil volume calculations. However I doubt that's the direction that you'll take.

I've not been to any of those exotic locations (I'm not counting Baja as exotic), but I have been racing for decades and desert racing for over a decade. I've been over Saline Valley Rd several times and I'll take it any day over the road into El Arco, at least as it was the one time that I've been over it ('01 B1k). The twin-tubes that I've seen faded never come back to 100%. Every fading event further reduces their ability to damp. I suspect that if you go back to twin-tubes that you'll find that deflective disc, high pressure damping has spoiled you and raised the damping bar beyond what a twin-tube can do.

Am interested to hear the results of your next step.

 

[Bat]

I was maybe 15 miles into medium grade washboard at around 25 mph when all of sudden I smelled oil and smoke

This is just not right and I think Bilstein would be very interested to see what happened. I would skip the tech guy and go straight to management and see what he has to say.

In my distant travels I have learned that most failures in the field result from straying from original design and especially overloading above payload.
You say the front end is very heavy and maybe the sprigs are just not up to it anymore, have you measured the shock length to see if that could be a problem.

 

[ThinAir]

Gene, if you're front springs were like mine, and I'd imagine they are or worse given what you've put your truck through, you're getting just 2" or less of shock stroke before you are hitting the stops. I'm no engineer but cycling a shock over just 2" thousands of times over in a short period of time would seem to build heat much quicker over a short stroke vs. say double that. No time for the shock to cool itself. Just a hunch here. If you're looking to replace your factory springs, you might want to consider a very minute albeit important lift of a couple of inches. You'll improve ride quality, shock stroke use, and pick up some articulation.

 

[generubin]

Hi ThinAir,

Thanks for your comments, but actually, to travel longer excursions, thousands of times in the same time period would be faster velocity, not slower. I rarely ever bottom my stock suspension and never so on washboard. In reference to modifications, in my many years as a pro mechanic and plenty of field service repairs of vehicles in rough conditions (never my own, other peoples) I have seen lots of problems with aftermarket mods. Any modification from stock comes with a whole host of other side effects. Any lift, at the very least puts u joints and/or cv joints at much weaker angles. Geometry often goes out beyond the ability to align and steering components can be strained.

The stock Ram 2500 has surprisingly good articulation. In this video you see the Dodge keep all 4 wheels on the ground. Later in the video the Jeep and Tacoma both lift wheels making for poor control (luckily they are going downhill do they do not get stuck).

Funny, so many of those Vanagon guys love to take pictures with their vans lifting a 4th wheel, I cringe when I see that!


After 40 years of thousand of miles with no problems with twin tubes and then going through two sets of 5100's in just a few hundred miles, I'd say I've done the acid test. I'm back to twin tubes, expecting many thousands of reliable service as I have had over the last decades.

Geno's has kindly accepted back my oil soaked shocks and refunded my money. Hat's off to Geno's Garage!