I know there are already a gazillion threads on this topic for our notorious lower ball joints, but I thought I would share my findings and get your thoughts and experiences on this issue. I had the chance recently to inspect some Raybestos lower ball joints. They came in a generic white box with a Raybestos sticker on it, but the actual joints themselves are branded Sankei 555. Many people claim that Sankei is the manufacturer of the OEM joints, and as such, they are good quality. I will argue against this as I've also had the opportunity to compare brand new Toyota OEM joints with the Sankei. As some background info, it appears that these Sankei 555 joints are also resold by Moog, Raybestos, Napa Premium Chassis, and Beck/Arnley.

When I inspected the Sankei 555 joint, I was impressed by the greaseable design and also the fact that the dust cap had a little opening for excess grease to come out. However, that was where my positive impressions ended. The dust boot itself felt thin (like it could puncture easily) in comparison to the NOK japanese branded rubber boot on the OEM joint.

I'm no grease expert, but I'll also comment on the grease differences between the OEM and aftermarket joints. The aftermarket joint has a yellow sticky grease (as pictured) which resembles the generic lithium grease you would get when you buy a grease gun and they give you some free grease. This transparent color suggests to me that this grease does not have much in terms of extreme pressure (moly) additives. The OEM joint uses a white grease which appears to be soap (sodium) based. If it is indeed a soap grease, then it would have excellent water repelling and shock loading properties, as well as being very "sticky" in regards to not being pushed out from contacting surfaces. Once again, I am not a grease expert so don't take my word on this. Just my observations and thoughts.

However, the most troubling finding is the movement of the joint itself. When I moved the ball piece, I noticed a TERRIBLE amount of resistance. Almost as if the ball was grinding inside the socket. It just FEELS like metal on metal contact and in my opinion, this will cause heat buildup and wear. And it is NOT a smooth type of resistance either. It was notchy, uneven resistance. In comparison, the new Toyota OEM joints have a smooth fluid movement.

I was curious as to what causes so much uneven resistance so I took the grease boot off and inspected. What I found was that the ball had a grease channel cut in to allow for grease to be evenly distributed inside the joint. The OEM ball joint does not have this feature. This grease channel could be what is causing the grinding. I cannot say for certain, however.

But what I DID find was very interesting. I will let the following pictures speak for themselves:



Note the scratches/scuff marks on the ball? I literally created those scratches on the fly JUST BY MOVING THE BALL IN THE SOCKET at most maybe 20 times. So if I was able to create those scratches just by moving the ball by hand, imagine what is happening when these joints are installed on a moving vehicle and the suspension is constantly going up and down. I did NOT notice this to be a problem with the Toyota OEM joints.

This can't be normal, so I would like to hear your experiences and opinions of these Sankei 555/Raybestos/Napa/Moog joints. Is this the final nail in the coffin as to why you should only buy OEM? Am I overreacting?