Moog Control Arms: CK, K, or RK?

Moog K, CK, r RK Difference

Moog Stamped Arms

Moog Control Arms: CK, K, or RK?

CK, K or RK? We here at Diverse Suspension Technologies get this question a whole lot. If you are putting parts on your vehicle, you want to know exactly what you are installing. It can be hard to do that with all of these letter designations. So here is all that you need to know to clear up the confusion.


Moog Stamped Arms

CK (K): Moog Problem Solver

Starting with the CK and K. Whether you see a “K” designation or a “CK” designation, you are getting the same part. The CK and K are Moogs Premium line of control arms. Utilizing their “problem solver” technology, these control arms address common factory design issues providing a better than original replacement for your vehicle. Most CK and K control arms include ball joints that are powder coated metal with gusher bearings giving them a long life. These ball joints are serviceable and have grease fittings. The CK and K arms also have problem solver bushings and a precise fit and form for easy installation.


Moog Forged Arms

RK: Moog R Series

The RK series is a more value driven part. Because there are so many different vehicles both foreign and domestic, Moog has introduced the R-Series arms to provide replacements for a wide range of vehicles. The RK arms have OE fit and form geometry alignment, with pre-installed OE style bushings and most include the ball joints. However these ball joints are not serviceable like the CK arms. All of the R Series arms have Moog validated construction and design, providing a less expensive alternative.


Moog Stamped Arms

Type and Warranty

Each line of control arms has Forged Steel, Stamped Steel, or Forged Aluminium arms to provide the best style for your specific vehicle. The Premium CK line has a limited lifetime warranty, and the RK has a 3 year warranty that are both handled through our awesome customer service team at DST. Whether you are looking for a “light on the wallet” OE replacement, or a “premium” control arm upgrade, Moog control arms are a great choice for your vehicle.



Comments

    1. Profile photo of Chelsea BakerChelsea Baker

      Hello Edwin! With control arms specifically, Moog offers a limited lifetime warranty for their CK line and a 3 year warranty for their RK line. If you have purchased from us here at DST, just give our awesome customer service team a call (1-888-406-2330). They may ask you a few questions and for some pictures to get a better understanding of the issue. Then once the defective part is on it’s way back to us, we will have Moog send out the replacement part.

      Have you purchased Moog parts before? If so, what has been your experience?

  1. Stephanie

    I am very disappointed with the r series control arms. I am on the second set and needing to get the off my car yet again! They don’t even last more than three months before they are squeaking and need to be swapped out again. Lifetime warranty yea but that doesn’t cover getting them changed every few months because they are a garbage product. Made in China surprise. This time whe I take them off I’m not making the mistake of putting another set on.

    1. Profile photo of Josh DanielsJosh Daniels

      Hey Stephanie,

      Sorry to hear about your experience with those control arms. We know that a squeaky suspension can be super irritating.

      It’s possible that the problem could be environmental instead of with the part itself. Generally, water or other contaminates getting into the bushings is the leading cause for a squeaky control arm and a little lubrication can usually clear that up, but there could be other factors at play. We sell a good deal of Moog parts to a lot of satisfied customers so we like to get to the bottom of any complaints about one of their products.

      If you would like to give our customer support line a call at 1-888-406-2330 and ask for our onsite ASE mechanic maybe we can get some more details and help you cut that awful noise.

      1. Stephanie

        Actually the bushing itself is wearing away. This is only after a few months. The first set I thought maybe was a defective part except both sides were the same. So I get the warranty second set and it’s been maybe four months and here we are again. Same issue. And it’s not installed incorrectly because installer is L1 cert control arms are not rocket science to install.

        I am very disappointed with the r series control arms. I am on the second set and needing to get the off my car yet again! They don’t even last more than three months before they are squeaking and need to be swapped out again. Lifetime warranty yea but that doesn’t cover getting them changed every few months because they are a garbage product. Made in China surprise. This time whe I take them off I’m not making the mistake of putting another set on.

        1. Profile photo of Josh DanielsJosh Daniels

          Hey Stephanie,

          We are right there with you about those rubber bushings. They can provide a smooth ride and provide a barrier between the metal parts on your vehicle but they just don’t last. Polyurethane bushings can provide better handling and should last the life of your vehicle.

          Rubber Vs Polyurethane

          It sounds like you’re putting your vehicle through a lot so you might consider looking at a hardier bushing set. Here is a blog post comparing rubber and polyurethane bushings if you would like some more information. I hope this helps.

          Has anyone tried replacing some worn out rubber bushings with polyurethane? How did it turn out? We would love to hear about it!

  2. Pingback: Rear UCA is shot, help! - Page 7 - Jeep Liberty Forum - JeepKJ Country

    1. Profile photo of Josh DanielsJosh Daniels

      Hey Patrick,

      Both of these parts actually use a Moog certified, stamped steel frame. The main difference between these parts is the ball joints that are installed in them.

      The CK version contains the Problem Solver ball joint which has the greaseable zerk fitting, full-ball metal stud, gusher bearing technology, and other patented improvements on the OE design.

      Thanks for the question and keep ’em coming.

  3. Danny

    Regarding the CK and RK LCA’s, is there a difference in the bushings installed in each?

    My OEM LCA bushing regularly gets oil dripped on it so I’m wondering if they’re both rubber or something more oil resistant?

    1. Profile photo of Chelsea BakerChelsea Baker

      Hello Danny!

      Great question! Most, if not all, of the bushings in both the RK and CK control arms are made of rubber. If you’re looking for something more resistant I would suggest going with polyurethane.

      Polyurethane is resistant to heat, road chemicals, other oils, and UV rays. It’s also wear resistant opposed to a rubber bushing which can be damaged after repeated flexing and stretching. Another pro for polyurethane is it should last the life of your vehicle while rubber has the same lifespan as the original (OE) bushings. There are pros and cons to both and if you would like to learn more about it head over to our Rubber vs Polyurethane Blog. Or if you’d like to call or live chat our amazing customer service team they would be happy to answer any questions you may have.

  4. Andrew Crouch

    Side note about the use of poly in some applications over rubber:
    I will bring up the topic of usage of polyurethane strut rot bushings in classic / vintage cars such as the 1971-1973 Ford Mustang and Mercury Cougar, or the 1972-1976 Ford Torino and Mercury Montego, or the 1972-1979 Ford Ranchero.
    Based on a lot of recent discussion in the last decade or so, there have been catastrophic failures from OEM strut rods {In this case, the “strut rod” is a solid bar threaded at one end for a MOOG K8207 bushing set, and the other end is bent with a pair of holes for being bolted to the lower control arm.} utilizing polyurethane and not allowing for the flex or give permitted by the original rubber design. In the case of most older cars that have been upgraded over the years and increased performance drivetrain and aftermarket big brake systems, the OEM strut rods tend to have failure if poly material is selected.
    This is merely a precautionary statement.

    I will say that for control arm bushings, and related, if the installed is not using the supplied grease or using a grease specific to use with polyurethane material, you may experience squeaking.
    Be it a track car, or a classic Lincoln Mark V, make sure you follow the install recommendations.

Leave A Comment?

About The Author

Profile photo of Drew Taylor