Brian_C

Hi All - I’m replacing rear struts and plan to stick with OEM. I don’t want to replace the springs if unnecessary. Do springs lose integrity over time?

Thanks for thoughts!

hardtailer

Good question. Contrary to shock absorbers the springs don't wear in the sense that they change stiffness or collapse/sag over time. They might settle a little at the beginning of their service life but that's it.
Low quality springs can settle quite a bit, though.

The only thing you should check for is whether a piece has broken off at either (typically lower) end of the coil. This can happen when grit between coil and spring base has worn through the powder coating and rust has progressed so far that the spring breaks at that spot.
A giveaway sign for that is when the car is no longer level across the axle, I.e. left to right.
In that case the spring is to be replaced.

It is very good practice to change the yellow/brownish bump stops (made of PU) as they do wear and actually do far more than 'bump stopping' wrt body and wheel control.

FLT SIXX

Ha! I just got done replacing my struts. Factory original parts on a 2002 with 109,000 miles on it. I had zero evidence bump stops ever existed on three of the four corners and a couple crumbles of bump stop trapped up inside the boot of one corner - proof positive that they disintegrate over time. Even if they look intact, be sure to really inspect them and make sure they aren't just going to crumble at their first impact.

Bash Hat

How does the car ride with the new shocks? Just got a set of B4s and will be insing them in the new couple weeks.

FLT SIXX

I won't know till spring. It's a fair weather only cab and I just shoveled 3" of overnight snow off the driveway. In between meetings today I'm finishing up the last of the repainting of the Brembos that are all off the car. I used Koni Special Active's and replaced all the suspension links, control arms, tie rod ends, swaybar links and bushings all at once. Should ride like a new car! I bought it all worn out - I'm not going to know how to drive it after the alignment shop.

elwoodcg

This sounds eerily like me save for the caliper repainting. It’s in my radar though.

golock911

When I first started looking at suspension options, I measured the height of my chassis to ground. The US spec is 157mm +/-10mm. My car measured 137mm to 141mm. This is lower than the ROW spec, albiet within tolerance. The funny part is that visually, the car looked really high. But this may be biased from looking at all the cars posted on Rennlist, where most have been lowered in some way.

Bump stops? Crumble city. Replace them.

Whatever you do, you will notice a significant improvement.

Brian_C

Great responses everyone! Kind of figured the springs wouldn’t lose integrity unless rusted. Appreciate the guidance. Yeah, bump stops are a given to be replaced.

I’m just replacing the rear struts as the PO had a complete overhaul of the front. Seems many of the components aren’t necessary to replace (arms and such). But the components will be inspected including the upper mounts. I don’t understand why the PO replaced EVERYTHING up front except the upper mounts - I found the bushing had failed on one and replaced it. Can you imagine spending 5k for a front overhaul and get it back with a rattle up front?

Hazmat1071

Does anyone have a link to the front/rear bump stops I should be getting when fitting KONI Sport shocks and struts with an Eibach Pro-Kit Spring Set?

I found these online, but am not certain:

Fronts:
https://www.pelicanparts.com/More_In...Y#backToTopAnc

Rear:
https://www.partsgeek.com/catalog/20...bump_stop.html

FLT SIXX

Those are all correct / will work. When you do the Koni swap they tell you to save/reuse your factory bump stops. These are to OEM specifications. You're good.

CraigT!

Having a set of the Techart lowering sport springs installed on the 991.1 base/non PASM next week. While having these installed I am having the shop swap out the OEM springs and install Bilstein B6 strut/shocks that I have ordered. Can't wait for the results

pulpo

excellent info, ty. going to be replacing my struts down the line, and will inspect the springs and replace if damaged.

my question is, how about the mounts? I see a lot of people replace them, especially in the front. Is there are a way to tell if they've worn or are they something that should be replaced at this age? Front and rear?

Other than bump stops and possibly top mounts, any other components within the coil-strut assembly?

hardtailer

I would replace the top mounts (incl the thrust bearing on the front struts) when replacing shock absorbers.

wdb

Agree. I'd also go with the shorter, RoW sport suspension bump stops when using lowering springs. You don't want to get into them too soon.

pulpo

great to know. thanks guys.