Passat or CC aluminum steering knuckles and LCA to save weight

PRY4SNO

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Edmonton, AB
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2013 Touareg Execline
Read an article the other day that suggests we can bolt on aluminum steering knuckles and LCAs from a CC or Passat. This would benefit our cars by reducing mass, lowering centre of gravity and increasing rigidity.

Asking around a bit it would seem the only potential problem could be introducing an offset issue. The article made no mention of this so I'm wondering what you guys think?

What exact year range would this be for compatible parts? 2006-2017 is what it says in a pic in the article, is that common between the CC and Passat?

 

Wilkins

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05 Jetta Wagon 5sp, 10 Sportwagen 6MT
This is a mod I’ve been researching. What I read is that the cast steel knuckles are prone to bending when subjected to extreme loads. The cast aluminum knuckles are stronger and identical except that the offset to the tie rod connection is slightly less. This results in slightly faster steering response, ie the front wheels turn a bit more for a given steering wheel angle. As a result an alignment is needed after fitting- no kidding LOL.
The knuckles from a CC, B6 Passat, or mk6 GTI are aluminum. An NMS Passat is quite different and won’t work. The brake carrier mounting bolts also have to be replaced since the aluminum knuckle is thicker.
The reason I’m interested is my alignment won’t come into spec left front, and I suspect the knuckle is bent as a result of sliding into a curb some years ago.
 

PRY4SNO

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Interesting, and good info, thanks. Especially about the brake carrier bolts.

The article's author was upgrading a mk6 GTI so I don't know about that particular platform having aluminum steering knuckles.
 

JELLOWSUBMARINE

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2011 Jetta Sportwagen, 6M, red/tan, navi, pano, 83 5m diesel pickup, 82 p/u trailer,.04 5.5 TDI Passat wagon (gone), 80,81,82 diesel p/u (gone), 80,82 sportruck (gone), 59 passthru bus (long gone), 79&87 westy (gone), 57 baja bug (long gone), 73 914
Has anyone here done this major weight reduction? I wonder how much it would effect mpg?

Rotating unstrung vrs unstrung.

I wonder if somehow there is a sweet spot, like when lightning flywheel, too light can have some effects on things you might not expect,
 

PRY4SNO

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@JELLOWSUBMARINE The mpg would be a tertiary benefit and quite minimal. There's more than a 10kg difference in fuel load during the course of a full to empty tank of diesel. The main benefit would be handling characteristics and then secondary would be less wear and tear on consumables.
 

JELLOWSUBMARINE

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2011 Jetta Sportwagen, 6M, red/tan, navi, pano, 83 5m diesel pickup, 82 p/u trailer,.04 5.5 TDI Passat wagon (gone), 80,81,82 diesel p/u (gone), 80,82 sportruck (gone), 59 passthru bus (long gone), 79&87 westy (gone), 57 baja bug (long gone), 73 914
At first abit counterintuitive how the TT spindles aren't as quick as the s3/passat. but it makes sense as it was designed for a wider car. My son just did the front wheel bearings on his outback. He was amazed at how ez it was with his new bearing press kit. Maybe I can talk him into swapping the JSW:sneaky: What roughly does a set of s3 arms & knuckles go for $?
 

PRY4SNO

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2013 Touareg Execline
@JELLOWSUBMARINE From my searches on car-part.com it looks like they've gone up since the early days (gauging by that thread @Wilkins linked). That may be a domestic thing up here though. Most stuff is cheaper in the US.
 

PRY4SNO

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I doubt you'd notice any difference in fuel economy.
Pretty much zero chance.

What's your take on installing CC knuckles and LCAs? Any potential issues with offset or things to keep in mind other than as noted above with longer caliper bolts? Other parts worthwhile to swap at the same time?
 

Tharkhold

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Jul 27, 2020
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NCR
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Mk5
I've done the conversion on both the front and rear. Gas mileage difference? Nil, or quasi nil.

Lighter/quicker driving/steering: yes, but it's NOT earth shattering.

I also have the Boxster 986 front calipers on mine along with 2-piece rotors as well, so I save another 3-6lbs per front corner.

Bottom line: is it worth it? If you can get the knucles at a u-pick yard for 15-30$ each? Yes. Don't forget that you WILL need different mounting bolts as the Al parts are thicker and you will need longer bolts for things like the knuckle to strut link.

Stats: Rear knuckles will lose 3lbs per side, front LCA and knucles will lose approx 8lbs per side, total of 24lbs.

If you need any hardware from the dealer, just state that the parts are for a 2008 passat/2012 tiguan FWD. If they insist, you can find a VIN online as well.

Bonus: Aluminium oxidizes alot slower than iron/steel... and it looks nice when new/shiny :)
Bonus number 2: the rear knucles will push your wheels out by approx 8mm per side.
Bonus number 3: if you use the passat/tiguan front lower control arm-to frame bushings, you'll lower the car by a few mm as well.

Not-so-bonus: you won't be able to mount 17LE/17z/18z porshe calipers on the front with Aluminium knuckles.

Nice and shiny-ish

 
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Tharkhold

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NCR
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Mk5
Here are a few parts for the conversion (some of these are the same parts as Iron/Steel, but since you're changing most of the parts, might as well get new ones):

Frontlist
3C0407253FLeft Aluminium KnucklePassat 2008
3C0407365BLeft ball jointPassat 20083 x Nuts-to-LCA per side (N10332002)
1K0423811KLeft Tie RodPassat 2008or Tiguan
3C0407254FRight Aluminium KnucklePassat 2008
3C0407366BRight Ball JointPassat 20083 x Nuts-to-LCA per side (N10332002)
1K0423812KRight Tie RodPassat 2008or Tiguan
3C0407151GLower Control Arm (Aluminium L/R same)Passat 20082 x Bolts: N10560702, 1 x Bolt: N10640301 (per side)
WHT000785Nut, wide, ball joint to Aluminium knucklePassat 2008Single use, 1 per side
5K0498621Front Wheel BearingAllneed 2
WHT005437Wheel Bearing to CV bolt, frontAllNeed 1 per side
WHT000237AWheel Bearing to Knuckle mounting boltsAllNeed 4 per side
N9116890112pt Bolt, Apikol/carrier braket to CaliperMostsingle use, 2 per sideREQ for 986 Conversion
N90954802BOLT. Strut. Mount. Shock. Passat 2008single use, need 2
N10106402Nut for abovePassat 2008single use, need 2N10106402x2
5Q0411315ALink. Stabilizer. Allneed 2
N90948802Bolt, Caliper carrier to knuckle // Apikol to knucleREQ for 986 conversion
Rear
3C0505433KKnuckle, LeftCC/Eos/Passat/Tiguan FWD
3C0505434KKnuckle, RightCC/Eos/Passat/Tiguan FWD
1K0505465AALink. Stabilizer. Bar. Suspension. All need 2
3G0598611ARear Wheel bearingAll need 2
N90648402 Bolt - Rear trailing arm bushing bracket to bodyAll need 4 per sideN90648402 x8
WHT000227Arm. Bolt. CONTROL. Adjust. Cam.All need 2
N91201301Bolt - Upper ctrl arm to rear bearing carrierAll Alsingle use, need 2N91201301x2
N10401801Nut - for Bolt - Upper ctrl arm to rear carrierAllsingle use, need 2N10401801x2
N10628401Bolt. Trailing. Arm. to rear carrierAllsingle use, need 4N10628401x4
N10628601Bolt. Arm. Mount. CONTROL. Rearsingle use, need 2N10628601x2
N10106402NUT. Lock. Arm. Mount. Cntl. - Rearsingle use, need 2N10106402x2
N10211202Hex Bolt - M12x1.5x90single use, need 2N10211202x2
N91076701Hex Bolt - M14x1.5x115 (Top of carrier)single use, need 2N91076701x2
WHT003467Hex Bolt - Rear shock to carrier - M14x1.5x70single use, need 2WHT003467x2
N9116890112pt Bolt, Carrier to Knucklesingle use, 2 per side
WHT007150Bearing to CV bolt, rear.AllNeed 1 per side
 
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Tharkhold

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Jul 27, 2020
Location
NCR
TDI
Mk5
Also,

when ordering parts like ball joints, ensure that they have the nuts for the aluminium parts.

The wide brimmed hat looking one installed on the below ball joint is the correct one for this application, the smaller nut is for steel knucles! Rockauto have some balljoints with both nuts, so order wisely.

 

Tharkhold

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Jul 27, 2020
Location
NCR
TDI
Mk5
Save yourself some hassle... these are 60$ each on rockauto (SKP SK520470 and SK520469), and they come with the bushing and ball joint already installed (triple check the description as some are incorrectly listed as w/ and w/o balljoints):

(note: you will need to get 2 x wide-brimmed hat nuts (WHT000785) from a dealer as these come with the 'wrong' ones)

 
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mnb009

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Joined
Oct 5, 2021
Location
Canada
TDI
mk6
Save yourself some hassle... these are 60$ each on rockauto (SKP SK520470 and SK520469), and they come with the bushing and ball joint already installed (triple check the description as some are incorrectly listed as w/ and w/o balljoints):

(note: you will need to get 2 x wide-brimmed hat nuts (WHT000785) from a dealer as these come with the 'wrong' ones)

Here are a few parts for the conversion (some of these are the same parts as Iron/Steel, but since you're changing most of the parts, might as well get new ones):

Front
3C0407253FLeft Aluminium KnucklePassat 2008
3C0407365BLeft ball jointPassat 20083 x Nuts-to-LCA per side (N10332002)
1K0423811JLeft Tie RodPassat 2008
3C0407254FRight Aluminium KnucklePassat 2008
3C0407366BRight Ball JointPassat 20083 x Nuts-to-LCA per side (N10332002)
1K0423812JRight Tie RodPassat 2008
3C0407151GLower Control Arm (Aluminium L/R same)Passat 20082 x Bolts: N10560702, 1 x Bolt: N10640301 (per side)
WHT000785Nut, wide, ball joint to Aluminium knucklePassat 2008Single use, 1 per side
5K0498621Front Wheel BearingAllneed 2
WHT005437Wheel Bearing to CV bolt, frontAllNeed 1 per side
WHT000237AWheel Bearing to Knuckle mounting boltsAllNeed 4 per side
N9116890112pt Bolt, Apikol/carrier braket to CaliperMostsingle use, 2 per sideREQ for 986 Conversion
N90954802BOLT. Strut. Mount. Shock.Passat 2008single use, need 2
N10106402Nut for abovePassat 2008single use, need 2
5Q0411315ALink. Stabilizer.Allneed 2
N90948802Bolt, Caliper carrier to knuckle // Apikol to knucleREQ for 986 conversion
Rear
3C0505433KKnuckle, LeftCC/Eos/Passat/Tiguan FWD
3C0505434KKnuckle, RightCC/Eos/Passat/Tiguan FWD
1K0505465AALink. Stabilizer. Bar. Suspension.Allneed 2
3G0598611ARear Wheel bearingAllneed 2
N90648402Bolt - Rear trailing arm bushing bracket to bodyAllneed 4 per side
WHT000227Arm. Bolt. CONTROL. Adjust. Cam.Allneed 2
N91201301Bolt - Upper ctrl arm to rear bearing carrierAll Alsingle use, need 2
N10401801Nut - for Bolt - Upper ctrl arm to rear carrierAllsingle use, need 2
N10628401Bolt. Trailing. Arm. to rear carrierAllsingle use, need 4
N10628601Bolt. Arm. Mount. CONTROL. Rearsingle use, need 2
N10106402NUT. Lock. Arm. Mount. Cntl. - Rearsingle use, need 2
N10211202Hex Bolt - M12x1.5x90single use, need 2
N91076701Hex Bolt - M14x1.5x115 (Top of carrier)single use, need 2
WHT003467Hex Bolt - Rear shock to carrier - M14x1.5x70single use, need 2
N9116890112pt Bolt, Carrier to Knucklesingle use, 2 per side
WHT007150Bearing to CV bolt, rear.AllNeed 1 per side

Hey, I've got a mk6 Jetta and im planning on doing the Passat Subframe, LCA and knuckles. I had someone tell me that 986 calipers won't fit on knuckles. What did you do to get them to fit?
 

mikerob97

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Feb 17, 2002
Location
Cary, NC
TDI
2014 Jetta Sportwagen
Had a question about this upgrade. I notice the above parts list includes the left and right tie rods. My question, are these require for the conversion? Thanks
 

Tharkhold

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Joined
Jul 27, 2020
Location
NCR
TDI
Mk5
Hey, I've got a mk6 Jetta and im planning on doing the Passat Subframe, LCA and knuckles. I had someone tell me that 986 calipers won't fit on knuckles. What did you do to get them to fit?
Wut? I can GUARANTEE that the 986/boxster non-s calipers fit on Aluminium knuckles... I have them on right now. You need to get apikol adapters though, with the appropriate mounting bolts and banjo bolts (banjos/caliper bolts are an available option if you order apikol brackets). https://apikol.com/product/apikol-boxster-brake-brackets-a3-gti-rabbit-jetta/

The person might have been referring to the bigger brembo 17LE/17Z/18Z calipers found on Tuaregs/Cayennes, which unfortunately don't fit on the Aluminium pieces.
 
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Tharkhold

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Jul 27, 2020
Location
NCR
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Mk5
Had a question about this upgrade. I notice the above parts list includes the left and right tie rods. My question, are these require for the conversion? Thanks
"Yes". The tie rod situation is a bit of a mess, as depending on where you look, these fit pretty much all VW's from 2005.5 to 2021. Now, on parts.vw.com the 'correct' tie rods that fit on passats and tiguans (i.e. Al knuckles) is 1K0423811K/821K. The J parts don't list the Tiguan nor do they list the 2008 Passat. Play it safe and get the K ones.

Side note: rockauto is messed up for these as well, ensure the parts you're getting are the K ones.

EDIT: I UPDATED THE ABOVE LIST AS WELL.
 

Dalon

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Joined
Apr 6, 2015
Location
Ohio
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2006 MKV Jetta TDI 1.9L - 210k 2013 Passat TDI - 27k
This is a mod I’ve been researching. What I read is that the cast steel knuckles are prone to bending when subjected to extreme loads. The cast aluminum knuckles are stronger and identical except that the offset to the tie rod connection is slightly less. This results in slightly faster steering response, ie the front wheels turn a bit more for a given steering wheel angle. As a result an alignment is needed after fitting- no kidding LOL.
The knuckles from a CC, B6 Passat, or mk6 GTI are aluminum. An NMS Passat is quite different and won’t work. The brake carrier mounting bolts also have to be replaced since the aluminum knuckle is thicker.
The reason I’m interested is my alignment won’t come into spec left front, and I suspect the knuckle is bent as a result of sliding into a curb some years ago.
Do you know if the B7/MK6 jetta tie rods thread into the tie rod ends of the B6? I read Tharkholds list and he didn't list the tie rods, just the ends, so I'm assuming the tie rod ends of the B6 would thread into our B7/MK6 tie rods but wanted confirmation as I am acquiring all the parts for a full conversion.
 

Wilkins

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Aug 19, 2005
Location
British Columbia
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05 Jetta Wagon 5sp, 10 Sportwagen 6MT
I’ve done this conversion now, have to write it up. You don’t need to change the tie rod ends, just the nuts for both tie rods and ball joints.
 

Tharkhold

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Jul 27, 2020
Location
NCR
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Mk5
I’ve done this conversion now, have to write it up. You don’t need to change the tie rod ends, just the nuts for both tie rods and ball joints.

Aye, besides the obligatory nuts for Al parts, no. BUT as one is already taking all the suspension/steering bits apart for this conversion, and you NEED an alignment done afterwards, installing new parts just makes sense as everything is taken apart and within reach ($ allowing of course).

That and the fact that these new parts from rockauto are so cheap that it's worth it.

Edit: oh, and having new parts on hand allows you to go in 'fuk it' mode with a grinder just in case something is stubborn!

I'm looking at you F*%&$ING rear end links that have the ridiculous 6/12pt inner threaded stud that ALWAYS breaks off when trying to loosen the nut on these:

 
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squeaks

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Dec 31, 2021
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Madison, AL
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2013 JSW
Question for those that have done this, would the wheel bearings on the front knuckles need to be swapped over or would the bearings that came off of a 2007 Passat work for a 2013 Sportwagen TDI?
 

Tharkhold

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Question for those that have done this, would the wheel bearings on the front knuckles need to be swapped over or would the bearings that came off of a 2007 Passat work for a 2013 Sportwagen TDI?
The front wheel bearings are pretty much all the same in the VWAG cars. They would work, however, you need to get a new axle bolt, along with the 4 bearing-to-knuckle bolts. You can't reuse them. Total for the front end swap are 2 x wheel bearing to axle bolts, and 8 x bearing to knucle bolts.

Bearings sold from rockauto optionnaly come with the axle and 4 x bolts fyi. I beleive FAG and WJB ones come with the hardware. The last pair i got were the WJB WA513253.
 

Wilkins

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Aug 19, 2005
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British Columbia
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05 Jetta Wagon 5sp, 10 Sportwagen 6MT
I swapped bearings but I’m quite sure that was unnecessary. Gave me a chance to clean up the knuckles nicely though. I now have a spare set of bearings from a 2006 Passat with unknown mileage and abuse.
 

copenhagen

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Jan 14, 2022
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Denmark
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2.0 CFFB
Hi guys, did this conversion. Nice upgrade with the brakes as well. But now i have 20mm pr side where wheels sticks out on each side. What wheel speecs do u guys run to get them underneath the fenders? Im running Bilstein b12 suspension,
 

Tharkhold

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NCR
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Mk5
I have 17" RPF-1's for summer and the OEM 17" wheels that came with the car for winter. I have to use 2mm spacers in the front to clear the RPF-1's, and 5mm spacers for the OEM wheels.

I don't have any fender clearance issues since the wheels i use aren't that wide. I'd love to go up to the 18x9' RPF-1's though... for that deep dish feeling! I'd probably have to roll the fenders/enlarge them though.

But on your issue, with the conversion done, your wheels poke out an extra 20mm? ...or are your wheels poking out from under the fenders by 20mm?

Reason i ask is that the front conversion 'shouldn't' add any extra track width, unless you mixed and matched some TTS/TTRS/Audi stuff (lower roll point/center of mass, lower ball joints (TTRS), scrub radius change *could* affect the car/alignment so that all these changes would impact the track width... but idk). The rear carriers add approx 8mm per side.

Maybe tell us exactly what you changes (with part numbers).
 
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copenhagen

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2.0 CFFB
Hi, it’s not a problem on the front. Only on the rear. But it seems it’s a common issue since 3C0505433K and 434 it’s more likely 8 mm wider on each side.

but i cant figure out what wheelspecs i will have to run. I have 2 sets. Original Talladega 19 8x19 et 51
And 7.5x18 et 47 both of them sticks out approximately 20mm on each side.
 
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