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-   -   rear suspension noise over tar strips (http://986forum.com/forums/performance-technical-chat/53590-rear-suspension-noise-over-tar-strips.html)

Pdwight 11-22-2015 07:37 PM

for me

part number 98733104302

shows $193.99 each on Amazon

winter.k 11-23-2015 08:11 AM

Search using the TRW part numbers that Smallblock provided.


http://986forum.com/forums/uploads01...1448298327.jpg

Amazon also confirms this for the 986/TRW JTC1186 part:

http://986forum.com/forums/uploads01...1448298666.jpg

Pdwight 11-23-2015 05:40 PM

Wow
 
That is a really good price, I am replacing both mine this winter

BTW I have been told the 987 is an exact fit and much tougher for our 986 cars

steved0x 11-29-2015 06:52 AM

Quote:

Originally Posted by winter.k (Post 474360)
Smallblock,

Thanks for the equivalent part numbers from TRW. These are $110 (986) and $125 (987) on Amazon with free prime shipping.

I guess everybody is getting these as both part numbers are out of stock now... ;)

jpl2407 11-29-2015 08:33 AM

I got mine from parts geek

winter.k 11-30-2015 08:20 AM

I noticed they were out of stock, once I actually placed the order. I prefer amazon at that price ($122 each for TRW1316) so I don't mind waiting. I'll share once they are back in stock and ship out.

steved0x 11-30-2015 09:32 AM

Quote:

Originally Posted by Smallblock454 (Post 456208)
Hi,

for those located outside the US or not willing to buy from Pelican.

Porsche 987 part number: 98733104302 and 98733104303
is equal to TRW JTC1316, EAN number 3322937921805

Porsche 986 part number: 98633104307, 98633104306, 98633104305, 98633104304
is equal to TRW JTC1186, EAN Number 3322937753246

The 987 part seems to be a little cheaper than the 986 TRW part. Around 85 euro each.

Regards from germany
Markus

Do you have the TRW number for the front control arm? I believe it is part # 99634104306

Thanks,

Steve

winter.k 12-10-2015 07:58 AM

Quote:

Originally Posted by winter.k (Post 475050)
I noticed they were out of stock, once I actually placed the order. I prefer amazon at that price ($122 each for TRW1316) so I don't mind waiting. I'll share once they are back in stock and ship out.

Just got shipment notification 12/10, originally purchased on 11/28.

Pnut 12-11-2015 04:33 AM

So wait... when I look up JTC1316 (987 part) on Amazon, it says it won't fit my 2003 Boxster S. I can safely ignore that and assume it's a by-the-book warning and not actual fitment?

http://986forum.com/forums/uploads01...1449840727.jpg

steved0x 12-13-2015 08:08 AM

Quote:

Originally Posted by winter.k (Post 476100)
Just got shipment notification 12/10, originally purchased on 11/28.

Me too, just shipped out, mine ordered 11/30.

steved0x 12-13-2015 08:12 AM

Quote:

Originally Posted by Pnut (Post 476204)
So wait... when I look up JTC1316 (987 part) on Amazon, it says it won't fit my 2003 Boxster S. I can safely ignore that and assume it's a by-the-book warning and not actual fitment?

http://986forum.com/forums/uploads01...1449840727.jpg

According to some on the forum, for the backs at least, you can use the 987 part, which is (according to those same folks) is a superior part. I actually ordered both of the out of stock amazon versions (986 and 987), and the jtc1316/987 is what came in stock and shipped so I will be putting them on.

I will report back but it might be a while...

Pdwight 12-13-2015 08:45 AM

Eagerly
 
Awaiting your report on this

steved0x 12-14-2015 05:20 AM

Quote:

Originally Posted by steved0x (Post 476459)
According to some on the forum, for the backs at least, you can use the 987 part, which is (according to those same folks) is a superior part. I actually ordered both of the out of stock amazon versions (986 and 987), and the jtc1316/987 is what came in stock and shipped so I will be putting them on.

I will report back but it might be a while...

Actually I was just checking my Amazon and *both* the 986 and 987 came in stock and got shipped... my plan was to cancel one after the other one shipped.. They are both supposed to be here by tomorrow, so I can take some pictures post and see if we can figure out the differences...

Steve

winter.k 12-14-2015 07:27 AM

Steve, Good thing returns are so easy with Amazon.

Looking forward to seeing what you find by looking at the parts side by side. See if the ball joint feels/moves the same.

JayG 12-14-2015 08:00 AM

This may be a dumb question, but what are you referring to as "Tar Strips"

Pnut 12-14-2015 01:26 PM

Basically, they're expansion gaps evenly spaced in the roadway where a tough but pliable material (tar-based, I guess) can expand and compress with the weather conditions. They make the rhythmic double thud as first your front, then rear tires go over them at speed. The liquid tar that is used to fill in cracks as well as cold patches used on pot holes are also culprits. Infrastructure is on the out nation wide it seems.

JayG 12-14-2015 01:49 PM

Quote:

Originally Posted by JayG (Post 476580)
This may be a dumb question, but what are you referring to as "Tar Strips"

Quote:

Originally Posted by Pnut (Post 476601)
Basically, they're expansion gaps evenly spaced in the roadway where a tough but pliable material (tar-based, I guess) can expand and compress with the weather conditions. They make the rhythmic double thud as first your front, then rear tires go over them at speed. The liquid tar that is used to fill in cracks as well as cold patches used on pot holes are also culprits. Infrastructure is on the out nation wide it seems.

Thanks

That makes sense. I never heard them referred to as tar strips

Luckyed 12-15-2015 03:42 AM

Quote:

Originally Posted by steved0x (Post 476557)
Actually I was just checking my Amazon and *both* the 986 and 987 came in stock and got shipped... my plan was to cancel one after the other one shipped.. They are both supposed to be here by tomorrow, so I can take some pictures post and see if we can figure out the differences...

Steve

Steve,

What part of FL are you in?
It appears I am going to have to do my rears (on my 2001 base) and I can't decide to pony up and pay my indy or tackle the job myself.

Any chance you could give me your impression as to how difficult it was after you swap yours out?

Thanks in advance for any suggestions you may have.

jpl2407 12-15-2015 03:56 AM

Quote:

Originally Posted by Luckyed (Post 476653)
Steve,

What part of FL are you in?
It appears I am going to have to do my rears (on my 2001 base) and I can't decide to pony up and pay my indy or tackle the job myself.

Any chance you could give me your impression as to how difficult it was after you swap yours out?

Thanks in advance for any suggestions you may have.

After reading about the install on here I don't think it is a really hard diy job, I didn't have time to do mine, but, it only took my local dealer 45 minutes.

steved0x 12-15-2015 04:11 AM

I am in Lake City, about an hour west of Jacksonville and about 45 minutes north of Gainesville. Lake City is where i-10 and i-75 meet although I am a little south east of that intersection.

Where are you? Close by?


Quote:

Originally Posted by Luckyed (Post 476653)
Steve,

What part of FL are you in?
It appears I am going to have to do my rears (on my 2001 base) and I can't decide to pony up and pay my indy or tackle the job myself.

Any chance you could give me your impression as to how difficult it was after you swap yours out?

Thanks in advance for any suggestions you may have.


Luckyed 12-16-2015 03:17 AM

Quote:

Originally Posted by steved0x (Post 476656)
I am in Lake City, about an hour west of Jacksonville and about 45 minutes north of Gainesville. Lake City is where i-10 and i-75 meet although I am a little south east of that intersection.

Where are you? Close by?

I am not, sir.
I am down in Port Saint Lucie.
About 1-1/2 hours south of Orlando and 45 minutes north of West Palm Beach.

steved0x 12-16-2015 05:38 AM

Quote:

Originally Posted by Luckyed (Post 476776)
I am not, sir.
I am down in Port Saint Lucie.
About 1-1/2 hours south of Orlando and 45 minutes north of West Palm Beach.

FL is a tall state :)

steved0x 12-16-2015 05:43 AM

Quote:

Originally Posted by steved0x (Post 476557)
Actually I was just checking my Amazon and *both* the 986 and 987 came in stock and got shipped... my plan was to cancel one after the other one shipped.. They are both supposed to be here by tomorrow, so I can take some pictures post and see if we can figure out the differences...

Steve

They got here last night, I don't have a picture but I took then out of the box and lined them up. The end with the rubber bushing part looks the same on both, and the other end looks the same as well. The only differences seem to be:
  • The 987 part has a different bend around the fork looking end.
  • The distance between the bolts holes do not appear to line up exactly (but I want to test once I have some bolts or something that fit the holes exactly) - the 987 holes appear to be maybe 1mm further (a very tiny amount) apart than the 986 part. I will be able to tell once I get a couple of bolts that are the right size to fill the holes, it may be just that my eyeball lining up didn't match. Edit: they do line up exactly, pics coming tomorrow.

They both look very nice and shiny, Made in Germany with 986/987 part numbers and a small part where a part of some cast logo was removed.

I am going to Fastenal today to get some bolts and will try to take some pics tonight.

Steve

78F350 12-16-2015 07:44 AM

I replaced my trailing arms last night and as I was finishing, noticed that my rear sway bar bushings were worn enough to rattle.

Just a quick tip to people that are replacing the control arm/trailing arm:
While you are at it go ahead and get a pair of fresh sway bar bushings. They are relatively inexpensive, easy to install, and also make rear suspension noise over tar strips.

Luckyed 12-17-2015 04:06 AM

Quote:

Originally Posted by 78F350 (Post 476793)
I replaced my trailing arms last night and as I was finishing, noticed that my rear sway bar bushings were worn enough to rattle.

Just a quick tip to people that are replacing the control arm/trailing arm:
While you are at it go ahead and get a pair of fresh sway bar bushings. They are relatively inexpensive, easy to install, and also make rear suspension noise over tar strips.

Sounds like good advice.
Thanks!!

steved0x 12-17-2015 05:57 AM

Ok here are some pictures of the two different track arms to try and tell the differences.

Beside the differences in the shape of the arm, maybe the monoball/bushing end of the arm has stronger internals? By hand I can't get either of the bushing ends to flex so I can't tell that way.

Here are some photos showing the differences.

From this side they have the same outline, but the 987 part has more "ridges" for lack of a better word, where the 986 part is flatter in the middle with no raised parts (and I don't have a photo of the other side so I don't know if it is the same, I will check tonight)

http://986forum.com/forums/uploads01...1450363733.jpg

Here are two additional shots showing the end detail. The holes line up exactly, I got some M14 bolts to test this out and you can see them in these two photos.

http://986forum.com/forums/uploads01...1450363777.jpg

http://986forum.com/forums/uploads01...1450363791.jpg

This is a detail of the part numbers with some part (the triangle?) ground off.


http://986forum.com/forums/uploads01...1450363860.jpg

This is a top down shot, with the 987 part on top, you can see how the curve of the arm is different, the bottom arm (986) sticks out toward the top of the picture.

http://986forum.com/forums/uploads01...1450363939.jpg

This shot is with the arms turned over so the 986 arm is on top, showing the curve from the other side.

http://986forum.com/forums/uploads01...1450364066.jpg

These next two show the arms side by side, the arm with the "V" sharpie looking mark is the 987 arm.

http://986forum.com/forums/uploads01...1450364121.jpg

http://986forum.com/forums/uploads01...1450364145.jpg

Maybe over Christmas break I will get a chance to install these and I might have more feedback then.

Steve

Pnut 12-17-2015 06:04 AM

Sooooo... the 987 part may change the rake/ride height?...

Thanks for the photos.

steved0x 12-17-2015 06:24 AM

Quote:

Originally Posted by Pnut (Post 476884)
Sooooo... the 987 part may change the rake/ride height?...

Thanks for the photos.

I don't think so, mounting hole to mounting hole they are exactly the same length. I think it would take different springs to adjust the ride height. I don't know too much about those things though... :)

JayG 12-17-2015 06:24 AM

the thing that was ground off is a triangle with a P in it that denotes it is a genuine Porsche part. The one you have was sold aftermarket. Same part just not from a Porsche dealer. Part or all or the Porsche part number may be removed as well.

jakeru 12-17-2015 09:25 AM

Interesting comparison pics. I wonder if there is a weight difference. It looks like the 987 arm might decrease the maximum allowable back-spacing for the rear wheel.

Pnut 12-17-2015 09:30 AM

Hoping Brad will explain why he much prefers the 987 part for the 986.

Pnut 01-06-2016 03:34 PM

Quote:

Originally Posted by steved0x (Post 476883)
Maybe over Christmas break I will get a chance to install these and I might have more feedback then.

Steve

Did you go with the 987 part? Fit fine? Prolly hard to make a distinction between a worn factory part and a new upgraded one (to say one is better than the other if both were new).

steved0x 01-06-2016 04:54 PM

I actually am 3/4 of the way through installing the passenger side one tonight. I am using the 987 part because I heard it was better and also I feel the 986 part will be easier to resell if I don't send it back to Amazon. However unless it has a better monoball end (and the ends look exactly the same) I can't see any practical differences outside of the slight shape differences.

The old one was shot, I could easily move the end around with my hands, where I can't make the new one budge at all.

I had to stop for the night but will finish tomorrow and will post some pics and stuff as soon as I can.

Steve

steved0x 01-06-2016 04:56 PM

Quote:

Originally Posted by jakeru (Post 476907)
Interesting comparison pics. I wonder if there is a weight difference. It looks like the 987 arm might decrease the maximum allowable back-spacing for the rear wheel.

Interesting, I will take a look and see if I can tell a difference once I have one side new (987) and one side old (986)

Now I want to run down there and see right away :)

Edit: I looked and I don't think so, if there is a change in clearance it is only 1 mm or so (but then I guess this could be the critical mm when fitting some wheels...)

mikesz 01-07-2016 04:11 AM

I read somewhere there was a minor difference in suspension between the 96-97 986 and later cars. the change allowed for larger rims and tires. Perhaps the difference in shape allows for this?

steved0x 01-07-2016 11:15 AM

Quote:

Originally Posted by steved0x (Post 479059)
I actually am 3/4 of the way through installing the passenger side one tonight. I am using the 987 part because I heard it was better and also I feel the 986 part will be easier to resell if I don't send it back to Amazon. However unless it has a better monoball end (and the ends look exactly the same) I can't see any practical differences outside of the slight shape differences.

The old one was shot, I could easily move the end around with my hands, where I can't make the new one budge at all.

I had to stop for the night but will finish tomorrow and will post some pics and stuff as soon as I can.

Steve

I'm done with the passenger side and posted a DIY with pictures here:

http://986forum.com/forums/diy-project-guides/60057-rear-trailing-arms-replacement-guide-diy.html#post479144

tonythetiger 11-24-2018 06:02 PM

Quote:

Originally Posted by Jager (Post 413619)
Here is where your problem is:



http://986forum.com/forums/uploads01...1407471617.jpg



Replace this arm and problem solved.



My experience when my Boxster was up and off the ground and inspecting all the joints, I could not make this arm rattle or make any loose noise when grabbing and twisting it.



True dat


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