What's the current state of idler arms for our cars?

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giantpune

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While I'm all up in my car's steering and suspension on the front end, I was looking at replacing or rebuilding my idler arm. It looks like there's not an easy answer. From reading the past threads, I've come across a handful of parts, but it seems like all the ones that are great fits are discontinued.

Cugar parts reproduction, out of stock and backordered. https://secure.cougarpartscatalog.com/71idler.html?sessionthemeid=26
Moog K8165. correct fit and geometry. discontinued
Moog K8118. they say its the correct part, but guys are around here saying it's not right
ProForged 102-10076. Good geometry and fit, but Discontinued
NPD part #3355-1. correct geometry, but top hole needs to be slotted. Its currently available for order https://www.npdlink.com/product/idler-arm/148651
trans-am roller. available for order, expensive, and may affect how the steering wheel returns to center? https://opentrackerracing.com/product/trans-style-roller-idler-arm-1971-1973-mustang-cougar/
rare parts #20250. correct geometry, does not look correct. currently available. https://fcrcmachine.com/rare-parts-idler-arm-1971-1973-ford-mustang-mercury-cougar-20250/
ACDelco 45C1011. Rock Auto lists this as a part for our cars and its in stock. I haven't seen anywhere else online confirming the fitment.
CJ pony parts H18750. Shows in stock. But for some reason only works for manual steering. No idea why this one doesn't work for power steering. The one review says it changes the steering geometry and requires enlarging the mounting holes. https://www.cjponyparts.com/idler-arm-mustang-1971-1973/p/H18750/
scott drake D1ZZ-3350-AR. Item description says its for a 71-73 mustang with power steering. It is currently available for order. I cannot find any feedback from purchasers to know how well it fits.

I'd obviously prefer something that is as close to the original as possible. I have a milling machine and can handle slotting the NPD if absolutely necessary. If it would work, I'm not opposed to pulling the arm off the NPD unit and using it on the mounting bracket from my factory one.

What say the hive on this? Am I overlooking something or is it really this much trouble? For a while I was thinking that it was only the front urethane bumpers that were hard to track down.
 
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Hemikiller

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The Moog K-8165 is correct for cars with power steering. I was able to buy a NOS one one eBay about 4 months ago, I think I paid $135 for it and it was a perfect fit. They pop up all the time on eBay, there isn't one on there right now, but if you wait a bit one should pop up. One just sold today:
 
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While I'm all up in my car's steering and suspension on the front end, I was looking at replacing or rebuilding my idler arm. It looks like there's not an easy answer. From reading the past threads, I've come across a handful of parts, but it seems like all the ones that are great fits are discontinued.

Cugar parts reproduction, out of stock and backordered. https://secure.cougarpartscatalog.com/71idler.html?sessionthemeid=26
Moog K8165. correct fit and geometry. discontinued
Moog K8118. they say its the correct part, but guys are around here saying it's not right
ProForged 102-10076. Good geometry and fit, but Discontinued
NPD part #3355-1. correct geometry, but top hole needs to be slotted. Its currently available for order https://www.npdlink.com/product/idler-arm/148651
trans-am roller. available for order, expensive, and may affect how the steering wheel returns to center? https://opentrackerracing.com/product/trans-style-roller-idler-arm-1971-1973-mustang-cougar/
rare parts #20250. correct geometry, does not look correct. currently available. https://fcrcmachine.com/rare-parts-idler-arm-1971-1973-ford-mustang-mercury-cougar-20250/
ACDelco 45C1011. Rock Auto lists this as a part for our cars and its in stock. I haven't seen anywhere else online confirming the fitment.
CJ pony parts H18750. Shows in stock. But for some reason only works for manual steering. No idea why this one doesn't work for power steering. The one review says it changes the steering geometry and requires enlarging the mounting holes. https://www.cjponyparts.com/idler-arm-mustang-1971-1973/p/H18750/
scott drake D1ZZ-3350-AR. Item description says its for a 71-73 mustang with power steering. It is currently available for order. I cannot find any feedback from purchasers to know how well it fits.

I'd obviously prefer something that is as close to the original as possible. I have a milling machine and can handle slotting the NPD if absolutely necessary. If it would work, I'm not opposed to pulling the arm off the NPD unit and using it on the mounting bracket from my factory one.

What say the hive on this? Am I overlooking something or is it really this much trouble? For a while I was thinking that it was only the front urethane bumpers that were hard to track down.
Oh, there are some more trouble of unobtainable parts you could run in... The half inch bushings for the OE rear sway bar for example. But back to topic:
I went through this a few months and bought some different idler arms. The result of this experience is as our friends above already said:

The WCCC is a perfect fit and looks almost like an OEM, the price for the quality is unbeatable! Have it as a spare.

The NOS idler arms from MOOG (K-8165). It was once created from Moog as a better design of the original ones for our 71-73 Mustangs, but now obsolete. They are a perfect fit too and this is what I have on my car now.

The current idler arms of Moog (K-8118) do NOT fit, at least the power steering cars. First of all the holes on the front passenger frame do NOT align as most of the reproductions are the same. The geometry of the arm looks different too but that is not necessarily a bummer.

As I recall the pictures of the Scott Drake ones they are exactly the same as the current Moog Ones so I assume they would not fit.

There are some out there with the Number 18750, that where called to be a direct fit. They are NOT. I bought a NOS from TRW and it doesn't fit. The holes do not align and the geometry of the arm is completely different. Could be made to fit though.

For the one from Don I cannot speak - I only know he sells solely parts that are not crap and generally fit our cars well, he is also in direct contact with the manufacturers. It is the same concept as of WCCC. He is a great guy to deal with and doesn't bite, so ask him.

Just my 50 cents...
 

giantpune

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One more option is to rebuild yours if it's a factory original.
I'm not opposed to that. I have a press and I'm not afraid to use it.

I wasn't sure what the state of affairs is for bushings and whatnot. Do we have a list of what all's needed?
 
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This was shared with me at some point.

unsure if it has already been posted……

 

Hemikiller

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I'm not opposed to that. I have a press and I'm not afraid to use it.

I wasn't sure what the state of affairs is for bushings and whatnot. Do we have a list of what all's needed?

Came up with these bushings for the idler arm. It's been quite a while since I've done this, but these look correct. I ordered them last summer. I should have a factory idler in my parts pile that I need get off my butt and verify the fit.


 
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giantpune

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giantpune

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Heads up for folks. I got the in-stock email today that the one at cougar parts is available.
 
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I went for the Moogs. Different than the original, but the height location for the steering link pivot point was correct. Arm length too. I needed massage the holes a tad to fit and used the old one for it.
No matter if technically good or not (time will tell), I have found the finish of the Moogs products really poor. Some parts were even starting to rust inside the boxes. I've corrected that of course, but I was expecting something much better from this brand.

Here the arm during reassembly.

moog_idler.jpg
 
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I'm late to the party, but the one I used is from NPD 3355-1A ( I think, can't find receipt) BUT it needed the top hole slotted upward to fit. Other than that, no problems. I don't think there is any difference between PS or manual steering for the idler arm. My car was originally manual, but converted to PS and used the old idler for several years before getting replaced.
Many moons ago, I posted a diagram to show that although the shape of the arm my look different, it's the dimensions overall are what is important.
 

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RIBS

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I bought a suspension kit from P-S-T suspensions, and it fit perfect, matches the one coming off the car….
 

tpj71mach

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I bought my idler arm from Scott Drake Holley it looks lie the one I removed from the car thumbnail_image1.jpg thumbnail_image0 (1).jpg

I have not installed it yet but it looks like it will fit. The mount holes line up and the geometry looks the same overall.
 
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