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View Full Version : New suspension install, rear end feels bouncy



Tiger
06-01-2008, 06:06 PM
Did you cut down the bump stop in the rear end?

Did you replace the sway bar links?

Brandon J
06-01-2008, 07:04 PM
does anyone have a picture of the stock bumpstops, so I know what to look for ? I assume they are at the top of my shock - since the bilstein's have internal once, there is no risk that I will mistake the stock bumpstops for the new ones that I shouldn't be able to see, correct?
As you said there are internal bumpstops, so no adjustments can be made. YOu cannot use the stock foam bumpstops. There could be several reasons why you have this feeling. First, you are not use to it. Second, give the suspension a month to settle in. Third, you said there might be some mismatched issue, perhaps rear steering and that signifies perhaps bad pitman arms (dog bones)....even if you recently replaced them, check to see if the boots are bad. Fourth, could be a combination of sorts. Good luck with finding the reason.

Brandon J
06-01-2008, 07:11 PM
dogbones were replaced at the same time as the shocks - one week ago. maybe it's my tie rods...

it IS possible to still use the stock bumpstops with bilstein shocks....they just need to be trimmed. mine are still there, but are not trimmed.

the not used to it thing is something i have considered as well, but on my other lowered cars, i never had this issue.

You just solved your culprit. Stock bumpstops will fit, but should they should not be with Bilstein Sports. You should leave the stock bumpstops out. You are riding on your bumptops on bumps and limiting shock travel.

repenttokyo
06-01-2008, 09:04 PM
so i've installed a new suspension: eibach lowering springs and bilstein sports all around. I replaced the upper rear shock mounts, dogbones and the spring pads all around as well. The suspension is much, much firmer than before.

Since the install, at highway speeds when I cross things like expansion joints or bumps the rear end feels a bit out of control - a lot of up and down motion that was not present before the change. Is this normal? i need to replace the tie rods in the front, and they are on order, but I don't think this can relate to the feeling I am getting from the rear. Is it possible that my new suspension is revealing some previous weakness in my car that I was not aware of?

any help would be appreciated.

bad_manners_god
06-01-2008, 09:59 PM
Is it your body that is experiencing the up and down motion or is it the car?

I've been in my friends skyline with coil-overs at the stiffest setting before he got bucket seats and i thought we were going to die....

After he got the bucket seats i thought we could make any corner.

repenttokyo
06-01-2008, 10:03 PM
it literally feels like the rear end is not following the front. This only occurred after I had the car aligned and the shop loosed the front tie rods to do so - the center link and tie rods all need to be replaced. Is it possible that this looseness in the front is contributing to the out of control feeling at highway speed in the rear?

bubba966
06-01-2008, 10:17 PM
That sounds to me like what people say happens when your rear subframe bushes are shot. Probably are noticing it now because of the new suspension parts aren't worn and have no slop in them. And your old parts probably had a bit of slop in them that hid the subframe bush problem.

repenttokyo
06-01-2008, 10:26 PM
That sounds to me like what people say happens when your rear subframe bushes are shot. Probably are noticing it now because of the new suspension parts aren't worn and have no slop in them. And your old parts probably had a bit of slop in them that hid the subframe bush problem.

rear subframe bushings were replaced when I purchased the car 1.5 years ago. I thought it could be that too, but it seems far too early for them to be bad.



Did you cut down the bump stop in the rear end?

Did you replace the sway bar links?

Sway bar links have been replaced front and back. But - I did not cut down the rear bump stop. I have talked to others running this setup, and they did not cut the rear bumpstop either. Do you think the rear bumpstop could be causing the issue? Is it easy to cut without removing the spring and shock together?

t.wak
06-01-2008, 10:38 PM
Did you change anything else on the car like tyres?

repenttokyo
06-01-2008, 10:39 PM
Did you change anything else on the car like tyres?

no. still running stock tires.

it could very well be that by not cutting the bumpstops I am not getting the full range of the shocks.

how hard is it to cut the bumpstops with the shocks installed on the car? is it even possible?

Sam-Son
06-01-2008, 10:45 PM
somethin is definitely ****ed up i have the same set up and i have no such problem

repenttokyo
06-01-2008, 10:51 PM
somethin is definitely ****ed up i have the same set up and i have no such problem


did you cut your rear bumpstops?

repenttokyo
06-01-2008, 11:01 PM
does anyone have a picture of the stock bumpstops, so I know what to look for ? I assume they are at the top of my shock - since the bilstein's have internal once, there is no risk that I will mistake the stock bumpstops for the new ones that I shouldn't be able to see, correct?

repenttokyo
06-01-2008, 11:20 PM
As you said there are internal bumpstops, so no adjustments can be made. YOu cannot use the stock foam bumpstops. There could be several reasons why you have this feeling. First, you are not use to it. Second, give the suspension a month to settle in. Third, you said there might be some mismatched issue, perhaps rear steering and that signifies perhaps bad pitman arms (dog bones)....even if you recently replaced them, check to see if the boots are bad. Fourth, could be a combination of sorts. Good luck with finding the reason.


dogbones were replaced at the same time as the shocks - one week ago. maybe it's my tie rods...

it IS possible to still use the stock bumpstops with bilstein shocks....they just need to be trimmed. mine are still there, but are not trimmed.

the not used to it thing is something i have considered as well, but on my other lowered cars, i never had this issue.

repenttokyo
06-01-2008, 11:41 PM
You just solved your culprit. Stock bumpstops will fit, but should they should not be with Bilstein Sports. You should leave the stock bumpstops out. You are riding on your bumptops on bumps and limiting shock travel.


it's ok to remove them completely?

This would explain the ultra firmness and the floating I have been experiencing.

Is there any way to remove them without using a spring-puller? i am not experienced with changing suspension components - it's such a bitch to do on a daily driver. is removing them a simple procedure?

Tiger
06-02-2008, 03:52 AM
Not possible to cut bumpstop while assembled. Do yourself a favor and buy new set of bumpstop... cut them back 2"... when you disassemble, rip out the old bumpstop any way you can... it is probably stuck inside that white tube.

attack eagle
06-02-2008, 04:19 AM
question, you said you had it aligned, mind sharing the rear toe and camber settings?
Won't explain the jounciness (which my colleagues have probably figured out for you) but could explain any other unsettled feeling.

Finally, it may seem an obvious question, but... you did not do more than loosely tighten the bolts until the car was on the ground and had been rolled/bounced to settle the suspension, right?

Brandon J
06-02-2008, 08:44 AM
it's ok to remove them completely?

This would explain the ultra firmness and the floating I have been experiencing.

Is there any way to remove them without using a spring-puller? i am not experienced with changing suspension components - it's such a bitch to do on a daily driver. is removing them a simple procedure?
All 4 Bilstein Sports have internal bumptops. You should remove all external bumptops. You can try to do this by jacking up a corner, place a jack stand underneath, then cut the foam off. Good sharp razors on a utility knife are good, or a good blade that can fit.

When I did my Sachs, I actually left the stock rear bumpstops in and trimmed them down little by little after determining how it rode with the travel. With Bilstein sports on the e34, the suspensions I have installed we simply did not use the external bumpstops.

Brandon J
06-02-2008, 08:57 AM
interesting - I didn't know it was possible to access the bumpstops while the shocks and springs were still on the car. thank-you for the tip.

I have heard tales of shocks mushrooming with no bumpstops on VW's using the bilsteins - the cars that you removed the bumpstops from entire never displayed any problems?

i appreciate your advice.

Nope. I actually rode in an e34 with someone who did not know not to use the bumpstops and they complained about the ride. It was bad. So we removed the bumpstops and they were real happy.

repenttokyo
06-02-2008, 09:04 AM
Not possible to cut bumpstop while assembled. Do yourself a favor and buy new set of bumpstop... cut them back 2"... when you disassemble, rip out the old bumpstop any way you can... it is probably stuck inside that white tube.


dealer wants 39 dollars for each rear bumpstop and 32 for the front - is it really necessary to replace them? The way brandon J is talking, I don't need them at ALL. Can I completely remove the ones in the front and buy new ones for the rear only?

repenttokyo
06-02-2008, 09:05 AM
question, you said you had it aligned, mind sharing the rear toe and camber settings?
Won't explain the jounciness (which my colleagues have probably figured out for you) but could explain any other unsettled feeling.

Finally, it may seem an obvious question, but... you did not do more than loosely tighten the bolts until the car was on the ground and had been rolled/bounced to settle the suspension, right?


i don't know the settings, I went to the same shop I always take my lowered cars to, so I don't think that's the issue - other than the very loose tie rods which are being replaced, along with the center link, on monday.

I didn't install the suspension myself.

Brandon J
06-02-2008, 09:05 AM
If I can get in there myself without having to take anything apart, I will do it this week.

I appreciate everyone chiming in here with advice - it's why I keep coming back to this site.

It's kind of unny - I used to have a stock 525. Now it's dropped and chipped - I guess that's what happens when you feel the addiction.

Haha, mine started out as a stock '93 525i stick. It all started with a chip. Then I added M3 cams, lightweight flywheel, diff, suspension, brakes, intake, etc. Then after that, came the S38 conversion. I have slowed down, but I always come back to the e34.

Tiger
06-02-2008, 12:55 PM
Yes, the front Bilstein Sport should have came with blue dust cover... so you throw away the factory white dustcover and the bumpstop. You reuse the conical washer and upper strut mount.

The rear, you must reuse factory white dustcover, and either completely eliminate the bumpstop or cut the new, or front old one. You must dig out the old bumpstop out of the white dustcover.

healtoeit
06-02-2008, 12:56 PM
You just solved your culprit. Stock bumpstops will fit, but should they should not be with Bilstein Sports. You should leave the stock bumpstops out. You are riding on your bumptops on bumps and limiting shock travel.
Do the front AND the back shocks have internal bump stops?

Tiger
06-02-2008, 12:58 PM
Brainstorming... If you don't want to disassemble the rear unit... What you can do is drill a hole... maybe 3/4" near the top... and chip away the bumpstop... clean out the bumpstops from bottom openings....

Lastly, reseal the hole with HVAC foil tape.

repenttokyo
06-02-2008, 01:05 PM
All 4 Bilstein Sports have internal bumptops. You should remove all external bumptops. You can try to do this by jacking up a corner, place a jack stand underneath, then cut the foam off. Good sharp razors on a utility knife are good, or a good blade that can fit.

When I did my Sachs, I actually left the stock rear bumpstops in and trimmed them down little by little after determining how it rode with the travel. With Bilstein sports on the e34, the suspensions I have installed we simply did not use the external bumpstops.


interesting - I didn't know it was possible to access the bumpstops while the shocks and springs were still on the car. thank-you for the tip.

I have heard tales of shocks mushrooming with no bumpstops on VW's using the bilsteins - the cars that you removed the bumpstops from entire never displayed any problems?

i appreciate your advice.

repenttokyo
06-02-2008, 01:18 PM
Nope. I actually rode in an e34 with someone who did not know not to use the bumpstops and they complained about the ride. It was bad. So we removed the bumpstops and they were real happy.

If I can get in there myself without having to take anything apart, I will do it this week.

I appreciate everyone chiming in here with advice - it's why I keep coming back to this site.

It's kind of unny - I used to have a stock 525. Now it's dropped and chipped - I guess that's what happens when you feel the addiction.

RallyD
06-03-2008, 10:06 AM
careful that you dont nick the strut shaft.
causes leaks and voids any warranty.

I have eibach/bilstein Sport and I know exactly what you mean. The front and rear jounce and rebound at different rates. It just doesn't feel right. Almost as if the rear rebounds too aggressively and passes the normal ride height point. I drive around the NYC metro area where the roads are less than perfect. On my last trip to Yankee stadium in the Bronx I literally caught air over a crest in the road. Ok maybe I was going a little too quick but I know this would not have happened with konis.
I do have bumpstops installed so I guell i'll pull them out and try again. I might use KYB in rear and BSports up front as I have various strut/springs floating around the garage.
I even had a friend drive the car while I drove next to it and indeed the suspension is not balanced front/rear. I am really disappointed and will try the free fixes but no way in hell am I buying another set of shocks for this car.
Its the story of my life apparently. On my PT I've had 5 different suspensions. Finally dropped the $ on KW coilovers and I must say I am not impressed. Too soft dampers. Progressive rate springs and the adjustable collar is now stuck on 2 of them. Eibach + Koni = FTW

Sam-Son
06-04-2008, 01:50 AM
damn im disappointed to hear this about the billie sports i have them and i dont notice anything like this....am i just not paying enough attention?

mamilapon
06-04-2008, 02:57 AM
no. still running stock tires.

it could very well be that by not cutting the bumpstops I am not getting the full range of the shocks.

how hard is it to cut the bumpstops with the shocks installed on the car? is it even possible?
Unfortunately youll have to start over! too far up
youll only need about 2.5 inches of bump stop.

attack eagle
06-04-2008, 03:59 AM
Nah, my rear rides beautifully.

RallyD
06-04-2008, 08:06 AM
damn im disappointed to hear this about the billie sports i have them and i dont notice anything like this....am i just not paying enough attention?
we should meet up. I would like to take a ride in your car.

Tiger
06-13-2008, 03:04 PM
So how did you remove those bumpstops?

repenttokyo
06-13-2008, 07:54 PM
update - cut the bumpstops out and problem is SOLVED!

thanks to everyone for their help!

repenttokyo
06-13-2008, 08:57 PM
So how did you remove those bumpstops?


i tried cutting them myself, but found it difficult with just one person to hold the bumpstop and cut through the springs. When I brought the car in to have the tie rods put on, I asked my mechanics to remove them for me, and using 4 hands they were able to cut them with the springs still on the car.