Hey guys,

I got my recently acquired 06 STR thoroughly checked by indie Jag tech (30yrs exp). Issue is my rear struts are shot. OEM CATS Jag struts are very costly, around 500 a piece. Since the suspension needs work, I want to install the HR Lowering Springs with 4 Bilstein HD (B6) shocks to really improve performance. I realize I would disable the CATS system.

I plan on getting the H&R springs from here:
Suspension Products for 2006 Jaguar S Type R

My issue is all the shock websites show the OEM Bilstein B4 series that came with the 06 STR. I want the B6 series and found them at these 2 websites but only list them for the 2000-2002 S Type.

http://www.nopi.com/dsp_part_detail....=180&vpcid=453

2000, 2001, 2002 Jaguar S-Type Shocks & Struts - Bilstein 24-067782 - Bilstein Heavy Duty Shocks

Can someone please provide a URL and/or Part number where I can get the Bilstein HD (B6 Series) for the 06 STR?

P.S. I saw someone post B6 aren't intended for lowering springs, that B8's should be used. Not sure how true that is, but if you have a URL and/or Part number for them too, it would be greatly appreciated.

Thank you.

 

Acemaster, you're trying to do what I already had tried. Bilstien is the manufacturer of the CATS struts and makes a ho-hum non CATS strut that fits the STR and S-Type Sport, these are what mine presently wear and are to be replaced by CATS struts. They don't have a B6 or B8 for the STR. Everyone else the same. My advice: The OEM rear CATS struts are $350+/each, not $500, do it.

 

this is good information. You just saved me some heartache, trying to go the route you already have.

Did you by chance try contacting Bilstein about rebuilding the struts, instead of replacing? I know there are other threads here that have suggested that, and it was on my list to do, but I haven't yet.

 

No wonder why I kept hitting dead ends searching for the B6. I was quoted around 500 to get OEM cat struts from Jag. Could you provide a URL where I can get them for 350? Since I want to install the HR lowering springs, should I do them at the same as the strut replacement? I think that might save on labor costs instead of having them done separately.

Name is Andrew. Not sure if I caught yours, thanks.

 

You have to pull the springs off at the same time to do the struts as they are mounted in the car as an assembly, so the labor time should be no different. Be aware, myself and a couple others had installed lowering springs with CATS struts (mine were OEM with ~50k miles) and got a CATS error which I was never able to get resolved. This resulted in the struts defaulting to full stiff mode; not a pleasant ride. I ended up switching to the non-CATS V8 sport Bilsteins (which I had to wait for the rears for 2 months as they were on national back order). On the flip side, there are more members with CATS struts and lowering springs with no problems; and with new CATS struts I would guess that you will be ok.

 

Are you referring to these: 06 2006 Jaguar Super V8 Shock Absorber - Suspension - Arnott, Front, Rear - PartsGeek

Is it safe to assume the non-CATS V8 sport bilsteins (on HR Springs) would give better handling then CATs OEM struts (on HR Springs)? Of course knowing how much better would be golden :-)

Thanks.

 

It sounds like if I put the H&R lowering springs with the OEM struts cats, it shouldn't be an issue according to you. I'm just a bit spooked because QuartzSTypeR mentions it disabled his cats system and made the ride very unpleasant so he used non-CATS V8 sport bilsteins.

Thank you for bearing with me while I go crazy with this decision lol.

 

Mina springs with factory CATS dampers here, and so far so good, no CATS errors.

I guess it's a hit or miss thing it seems.

You might as well put the springs on while replacing the dampers, otherwise you'll pay to do it twice. Shouldn't be any additional costs to install the lowering springs this way.

Are you certain the factory CATS dampers are shot in the rear?
Does the car throw any CATS errors?
Does the car or rear ride rough or bounce a lot ?

 

Sorry, just saw your edit.

No, I went with the Bilsteins for the V8 Sport suspension, not air ride (those are for an XJ, not S-Type). It would be difficult for me to comment on if the handling is better, since I only drove the car with the stock CATS suspension for a few months, then installed the lowering springs which caused the struts to go full stiff. I then went with the V8 Sport Bilsteins with the lowering springs; which obviously improved the ride over the full stiff CATS struts. I don't have a direct way of comparing stock CATS to stock V8 Sport Bilsteins, or lowered CATS to lowered V8 Sport Bilsteins. I would've preferred to stay with the CATS setup, but I have no problem with the V8 Sport setup, it is a slight bit more mild than the CATS IMO. These are the struts I went with:

Bilstein - KYB - Rancho - Monroe - Edelbrock Automotive Truck Shocks and Struts - Shockwarehouse.com

As I stated, others have done it without an issue, and there are a few (in the minority) that have had a problem when combining the lowering springs with the CATS struts. I was unable to find what the issue was and since I didn't have the tools to diagnose the suspension fault codes I took it to a dealer which told me to replace the struts and springs and couldn't/wouldn't tell me exactly what issue they found

 

To be precise, the rear left strut is "worn". It gives a lot so when going over bump, you'll hear clunk sound with to much bounce. Jag tech said you should always replace the pair. So that would be the rear left and right.

After thorough research I am definitely going with the H&R Springs.

 

Based on on the information presented by you and bfsgross, the recommendation would be to stay with CATs struts instead of the ones from shockwarehouse?

 

for my education, since I'll be following-suit here, can you tell me how you determined which strut was worn? How did you determine definitively that your CATS is working properly, and the shocks are simply worn?

My car shows signs of someone (previous owner) having done some suspension work, and I would hate to replace parts, only to discover that the parts are not worn, but that the CATS is not working correctly.

How does one test that the CATS system is functional?

 

Yes. I went with the non-CATS setup for 2 main reasons: 1. I didn't want to spend that much $ on new struts. People are saying $350/each, but I haven't found them for under $400/each. Either way, $1400-$1700 just for shocks on a ~$15k car is too steep for me. Plus, if you aren't doing it yourself, expect another ~$400+ in labor. I got my whole Bilstein V8 Sport setup for $400 new. 2. I didn't want to install my $1600 struts and have the same problem with the CATS error code and an uncomfortably stiff ride. All in all, I would've preferred the CATS setup with the lowering springs, but it just didn't make sense to me to spend that much money without being certain it would've fixed my problem.

 

Yeah, the decision you made for your situation definitely makes sense, I totally agree with you. Its likely I can get the left rear strut replaced at no cost but I would have to buy the right rear. If thats the case, I'll stay CATs. If I can't get the left rear cost covered, I would then go in your direction of getting all 4 from shockwarehouse (non-CATs) for $460 instead of spending almost a grand for the 2 rear OEM struts.

You mention Bilstein V8 sport setup is not for the S-Type. Bilstein BST HEAVY DUTY is from the the link you provided which would work for my car if I need to get them?

 

CATS is functional if you're not getting CATS error.

 

The link I provided is for the S-Type. The air ride ones I referred to were from the link you provided earlier for the "Super V8" which is not an S-Type, rather an XJ and I do not believe they would work on an S-Type.

 

Gotcha. Hey man, I appreciate all the time and information. You really helped me sort things out. This forum is great!

 

That's what this forum is here for .

 

I reported the symptoms of a clunking sound in the rear when going over bumps. I also noticed a lot of bounce. I brought it to an indie Jag tech (30yrs exp.) and after putting it on the lift he applied pressure to the wheel. Pushing on the tire in the upwards direction of the wheel well. Noticed there was way to much give.

Analyzing the strut, apparently towards the bottom of the shock (mount area) the bushing is no good. This is the cause of the issue. To save cost on repair, you can call around to find someone who'll order an individual part of the strut and do a "strut rebuild". Keep in mind, Jaguar doesn't sell the parts individually, you get the whole CATs strut (est $450) each.

He ran a very thorough diagnostic scan with the computer on the vehicle. The scan was so thorough that if someone reset the computer to clear an error code and didn't resolve the issue, the scan would detect it.

It reported no error codes or past error codes that may have been manually cleared, so the CATS system was working fine. Keep in mind if its currently malfunctioning, you would see the error on the dash.

 

thanks. I've seen no CATS errors, and had assumed it was just age & wear that made the car feel so soft, but I haven't done any in-depth investigation yet. I noticed last week that it looked like someone had been working on it, and it made me scratch my head abit.

thanks again.