T6.1 B14 Komfort rear knocking

IslandLife82

Member
T6 Pro
New to the forum so firstly hello.

I have just fitted a set of B14 Komforts to my T32 T6.1 and I have an annoying knock mainly from the rear near side over small bumps or changes in road surface. The adjusters are at the top of the spring as I know this is a common mistake. Everything is torqued up. Adjusters are 10mm off lowest setting. I have read that there were some issues with B14 dampers in the past but looks like these were cured.

I am interested if anyone else has had this or have any ideas. I’ve not tried refitting the old dampers yet to rule the dampers out.
 
Hello

Did you tighten up the rear suspension when it was under weight or suspended?
Needs to be torqued up when on the floor, and under weight.

The rear damper issue was many years ago on the B14 suspension.

HTH
 
It was tightened but not to torque spec then lowered and torqued on the ground. I thought that might have been too tight when it was taken off the Jack so I loosened and re-torqued yesterday but it made little difference. It seems to just be the near side making the noise.
 
Hello

Did you tighten up the rear suspension when it was under weight or suspended? Needs to be torqued up when on the floor, and under weight.

The rear damper isse, was many years ago, on the B14 suspension.

HTH

Is this specific to b14s or good advice for all suspension adjustments?
 
So following a helpful call with Bilstein it appears the old B14 issue with the T6 also affects some T6.1s and the B14 Komfort.
There are the 4 raised areas where the nut is spot welded to the chassis where the top of the rear damper fits. The top bush on the damper a larger diameter than the standard damper bush and due to this it is interfering with these 4 raised areas and preventing a good mating surface which is causing the bush to move slightly and cause the knocking noise.
Bilstein have said the 2 options are to grind down the 4 bumps, paint, and refit the damper or taper the bush so it doesn’t touch the raised bumps.
I will sort it out next week and report back in case anyone has the same issue.9AE1C698-C0A4-40C3-AAFD-DEBE00AEE9F2.jpeg
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Somebody will be along in a minute to tell you they are crap, throw them away and to fit what they recommend ;)

Glad you found the issue, I’ve read about those spot welds being an issue before somewhere.
 
I can’t fault the ride and built quality to be fair. I had some B6s on my Defender and they were shockingly bad so I replaced them with Fox 2.0 piggyback shocks which were amazing.
Only had the B14s on for a week but the ride is transformed with very little body roll and still very comfortable with it set to a 60mm drop. The bush issue is a bit of a pain but nothing to get stressed about.
 
Surely it's on Bilstein to sort and not you to start grinding your chassis? Your having to adapt your van to work with the suspension, or shave down a bush, so a shock designed for your van will work? I know where I'd tell Bilstein where to shove it.
 
I agree it’s not great considering to cost of the product. If it were a 5 minute job to take off again I would probably return the set and get something else but removing the 4 dimples doesn’t bother me as long as it is all surface treated before reassembly to stop any corrosion issues in the future.
Interestingly the chap at Bilstein said the bush is bigger due to in increased forces placed upon the bush as a result of the lower/firmer ride and they don’t intend on modifying the bush as it would reduce its strength.
Don’t shoot the messenger please! Remember I’m the new guy here.
 
I agree it’s not great considering to cost of the product. If it were a 5 minute job to take off again I would probably return the set and get something else but removing the 4 dimples doesn’t bother me as long as it is all surface treated before reassembly to stop any corrosion issues in the future.
Interestingly the chap at Bilstein said the bush is bigger due to in increased forces placed upon the bush as a result of the lower/firmer ride and they don’t intend on modifying the bush as it would reduce its strength.
Don’t shoot the messenger please! Remember I’m the new guy here.
I wasn't having a dig, was just throwing my two cents in. It's entirely your decision at the end of the day what you do, I just think for how much they cost it should be ready out the box.
 
Surely it's on Bilstein to sort and not you to start grinding your chassis? Your having to adapt your van to work with the suspension, or shave down a bush, so a shock designed for your van will work? I know where I'd tell Bilstein where to shove it.

But the welds are only like that on some vans, you can’t blame Bilstein for that inconsistency. No doubt companies that fit Bilstein all day long such as Bognor or THQ will just quickly grind the spots off before fitting.
 
But the welds are only like that on some vans, you can’t blame Bilstein for that inconsistency. No doubt companies that fit Bilstein all day long such as Bognor or THQ will just quickly grind the spots off before fitting.
Yes the guy from Bilstein said that they are aware that some of the Bilstein dealers just grind them off and do surface treatment before fitting. Once the damper is out it would be a 5 minute job to do.
 
Hi

Does anybody know if this also an issue with the T5.1

Just had a new set of bilstein b14 komforts installed and the rear end is knocking really bad

Thanks
 
We’ve never grinded a single weld off, or had knocking on B14K. Which is even more strange.

We worked very closely with Bilstein with the previous on the the B14. It turned out to be a faulty batch of dampers, although many claimed other issues.
 
Bilstein have agreed to send me some new bushes FOC but maybe there is another issue if there’s suddenly multiple issues popping up with the Komforts. @Dougie09 have you called Bilstein? I spoke with Louis at Bilstein 044 116 289 8345. @BognorMotors even though you haven’t had the knocking, have you had the damage to the bush like in my earlier photo?
 
Hi

I’ve not spoke to bilstein yet, I’ll give them a call in the morning after I’ve inspected my top mount and damper bushes.

thanks for the details @IslandLife82
It will be interesting to know what yours look like. I’m wondering now if there is a faulty set of dampers again rather than the welds being the issue as Bilstein have said. I have asked Bilstein and VanStyle for replacement dampers to try but all I have got so far is new bushes.
 
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