Rear trailing arms replacement guide DIY

[steved0x]

Originally Posted by petee_c

Steve, how's it been running with the 987 part?

Sent from my LG-D852 using Tapatalk

Been running great so far and is quieter than my old ones too

[texomawaves]

So.. Is the trailing arm ball joint end a common cause of rattles? I have a rattle when I go over cobble stone roads. If this is a common issue I think I'll replace mine.

[RandallNeighbour]

Originally Posted by texomawaves

So.. Is the trailing arm ball joint end a common cause of rattles? I have a rattle when I go over cobble stone roads. If this is a common issue I think I'll replace mine.

The answer to your question is yes.

[flaps10]

I thought I'd throw another data point in this thread since it's all about the same subject. I knew these parts under a different name: rear track arm (even though the very similar counterpart in the front of the car is called a trailing arm).

Anyway I went with these Porsche 986 987 Boxster Boxster s 97 10 Adjustable Rear Track Arm Arms | eBay
Not because I really needed the adjustment (though it certainly won't hurt) but because the pair of them were cheaper than a single OEM from the factory.

Rather than just replace the track arms (my left one was rattling on tar strips) I also replaced my lower control arms and my sway bar end links and bushings.

To the question above about whether you can swap them out with the car on a ramp I'm sure you could. I found it handy to have the whole mess free to swing back and forth while I got the bolts all installed.

Prior to installing the adjustable arms I pinned each of them to the arm I removed so that I could set them to the exact length and lock them down.

One issue with the adjustable arms is the fact that they're straight instead of having that dog leg in them like the originals. To answer anyone's question about why they might have a bend, it's to clear the inside forward edge of the tire. It's close enough that I'm ordering a set of wheel spacers just to make sure they never rub.

Mine is all back together so it's on to exhaust and then lift the front where I've got another set of lower control arms and complete tie rod ends (all OEM) and off to the alignment shop.

[texomawaves]

I'll be replacing with new TRWs. But thought I'd ask... Does anyone rebuild/exchange these?

[steved0x]

Originally Posted by texomawaves

I'll be replacing with new TRWs. But thought I'd ask... Does anyone rebuild/exchange these?

I think Vertex rebuilds them and replaces the monoball end with a urethane bushing. There is a thread somewhere that describes why (in that writer's opinion) it is a downgrade, because (I am trying to recall what the thread said) the urethane bushing allows some fore/aft compression which allows caster and toe changes under hard driving, where the monoball constrains the fore/aft motion due to the nature of the monoball style of joint. It made sense to me.

I don't know of anybody that rebuilds the OEM track arma and replaces the monoball end with another monoball.

[texomawaves]

I found the TRW JTC1186 for sale by a ebay seller "carpartsinmotion" in the UK for about half the price. It seems legit, but wondering if any pitfalls from ordering overseas like this to save a little money. Any risk here, thoughts?

Porsche Boxster Wishbone Track Control Arm 2 5 3 2 96 to 02 JTC1186 Suspension | eBay

[steved0x]

Originally Posted by texomawaves

I found the TRW JTC1186 for sale by a ebay seller "carpartsinmotion" in the UK for about half the price. It seems legit, but wondering if any pitfalls from ordering overseas like this to save a little money. Any risk here, thoughts?

Porsche Boxster Wishbone Track Control Arm 2 5 3 2 96 to 02 JTC1186 Suspension | eBay

$108.26 on Amazon prime for the US:

https://www.amazon.com/TRW-Automotive-JTC1186-Premium-Control/dp/B00T9YHFCE/ref=sr_1_1?ie=UTF8&qid=1466529491&sr=8-1&keywords=JTC1186

The UK one with shipping looks to be slightly above that plus who knows how long it would take to get there...

[texomawaves]

Thanks Steve. I just saw that deal on Amazon, and then another one for $189 also on Amazon. The large difference kinda spooked me away thinking it may be too good to be true. $108 + free shipping is the best deal so far. Thanks again!!

[steved0x]

Yeah I don't know why there are multiple prices/sellers on Amazon for the same thing...

[texomawaves]

wow, a 45 minute job on the right rear, with a beer break half way through. Now I hear all the rattles coming from the front of the car. I'm thinking the front track arm joints are worn out there too.

[Shred]

Just to add to the OP's excellent guide.
I've replaced mine yesterday.

I loaded the suspension using my jack to order to put the new part in.

I fully loaded the suspension and installed the front bolt very easily, then use the jack to lower the suspension if needed to install the rear fork section. The jack can help getting the perfect angle to install the part, it basically would slip in with just a little force.

Remember to use blue Loctite and a new locking nut at each rear end.

[BruceH]

Originally Posted by Shred

Just to add to the OP's excellent guide.
I've replaced mine yesterday.

I loaded the suspension using my jack to order to put the new part in.

I fully loaded the suspension and installed the front bolt very easily, then use the jack to lower the suspension if needed to install the rear fork section. The jack can help getting the perfect angle to install the part, it basically would slip in with just a little force.

Remember to use blue Loctite and a new locking nut at each rear end.

I did mine today, I used the 997 part. Great DIY write-up I will echo using your jack to load the suspension. Getting the suspension to just the right height allows the arm to slip right into place. I also ended up replacing the underbody panel and the two rear wheel mud guards. All three were well past their prime. The clunking is now gone for the most part. There is still some suspension noise but no where near what it was before.

[Raider]

Yes, thanks for the great right up! Got a pair today from Amazon in TRW box and Porsche part number still on them. I thought this after market stuff had the number ground off?

[steved0x]

The part number is still there, but there is a little triangle that is ground off on the TRW arms that is present on the Porsche arms. It might be where that little blemish is between "Outside" and the part number.

[Raider]

Thanks, maybe that's what I'm thinking of not the part number. But for $116.97ea. I can do without the triangle!

[Deserion]

Just did this job on mine this afternoon. It went much more smoothly than I had anticipated.

I went with the TRW JTC1316 (987 part) as they were a little cheaper at the time on Amazon compared to the JTC1186 (now they're opposite).

The wobble extensions were a good call, Steve. Did it one side at a time and got it all torqued nicely. And no more rattles!

[steved0x]

Originally Posted by Deserion

. And no more rattles!

Nice!

Always fun when a project comes together

[Need_for_speed]

Just replaced my rear trailing arms and many thanks to Steve for posting this DIY. It was really helpful. I thought I'd pass along a few observations in addition to Steve's excellent instructions.
After removing my old trailing arms, it was obvious they were shot. I could move the rubber bushings around easily with my fingers -- they were very loose and floppy. The new arms are very stiff -- couldn't move them at all.
FYI, if you're a old little guy like me, it's a lot of fun cranking those front bolts to 118 ft lbs while lying on your back. I kept rechecking my torque wrench thinking I had set it wrong, and also wishing I had a lift instead of jack stands so I could gain some leverage.
In the end, Steve's DIY helped a lot, and it wasn't all that bad of a job. The only problem now is that I've seen all the other suspension components with rubber bushings, and I know they need to be replaced as well.

[Danimal]

I had the classic clattering in the back going over rough ground at low speeds. So I changed the rear trailing arms with the 987 TRW part listed in this thread. It is much cheaper than the corresponding 986 part from TRW.

I did it with the whole car up in the air using lift bars. Had no problem aligning the bolts, just had to push a little on the lower control arm. I used the existing bolts and torqued them to spec (118ft/lbs). I did not use loctite but sort of wished I did. Oh well.

Took it on two test drives and the clatter is gone. Still can’t figure out what was wrong with the olds ones. But glad the commotion is gone 👍

Another great fix from the forums in the books! 📕