Kingpin Bearing Part Numbers And Availability..

[sponaugle]

I have a 1990 R32 GTR, and I need to replace the kingpin bearings. In digging around in many of the threads on this topic, there seems to be a general unavailability of the lower bearing.

Front what I have collected so far from these threads:

Upper Bearing Nissan Part Number: 40030-33P07

Lower Bearing Nissan Part Number: 40030-60U00

Upper Seal Nissan Part Number: 40579-33P01

Lower Seal Nissan Part Number: 40290-33P00

Proposed Upper Bearing Mfg Part Number: NSK-6204V or NTN-2N0804

Proposed Lower Bearing Mfg Part Number: NTN-6907LB

I pulled the arms off my car and took at look at the bearings, and I found the following:

Upper Bearing Mfg Part Number: NTN-6204LB (Not NSK-6204V)

Lower Bearing Mfg Part Number: NSK, BAT31-1B , S32 (Those were the three marks on the casing).

The Upper Bearing, if it is NSK-6204V or NTN-6204LB, is something easy to find. There are multiple online bearing places here in the US that have them. I can also order the part number listed above from Nissan ( 40030-33P07 ). It is listed as a part for the TT 300ZX.

The Lower Bearing I have is an NSK one, with what looks like a part number of NSK-BAT31-1B. I can't find a reference for that part number anywhere. If I look up the NTN-6907LB I do find some chinese sites that reference it, but nothing that looks ligit.

Here is what I am curious about: If I search for the Nissan part number listed above ( 40030-60U00 ), it is easy to find as it is a Nissan 300ZX part. I can order that from a dealer here.

In a few threads there is mention that the 'nissan part number' is not correct, although I have not seen a reference to exactly which part number everyone is talking about. I could just go ahead and order the nissan part and see what I get.

Does anyone have a definitive answer about the correctness of the two nissan part numbers? ( 40030-33P07 and 40030-60U00 )? Any other sources for the lower bearing?

Cheers,

Jeff Sponaugle

[sponaugle]

One other note: I measured both the kingpin and well as that lower bearing from my car and they confirm some other measurements I read online. It is a 31mm inside and 58mm outside. That is a pretty atypical size, especially the 31mm part. That may explain the BAT31-1B part number I see on it.

The 6907 number referenced above translates to a 35mm inside and 55mm outside bearing, regardless of NTN of NSK.

The kingpin part itself, at least for the 300ZX is listed as 40022-60U05. According to several online sources that is the correct R32 part number. If the 300zx and R32 part numbers are indeed the same then the lower bearing used on the 300ZX must also be 31mm inside diameter.. Of course that doesn't mean the outside diameter is the same!

One last option I could consider: There are some readily available 58mm outside and 28mm inside bearings of the same thickness and construction. It would be very easy to take the two king pins and have them turned down from 31mm to 28mm and use those bearings. Thoughts?

Jeff

Edited October 27, 2015 by sponaugle