NTN tapered roller bearings

Catalog examples include 4T-332/28, 4T-336/332, 4T-339/332 and 3230/500UTG. A shared part of a designation does not establish interchangeability. Copy prefixes, slashes and final letters from the marking or equipment documentation.

If the dismantled parts carry different markings, record both. Separate photographs of the outer ring and inner assembly help explain the requested scope. Do not shorten a compound designation to whichever number is easiest to read.

This family is used in transmissions and machinery assemblies with combined shaft loads. The direction of thrust and the relative arrangement of the supports matter when reviewing a replacement; the family name alone does not define them.

Explain whether you are replacing one bearing position or working on several supports. Report heat, raceway marks or loss of fit as observations without assigning an unverified cause. Identifying the replacement and diagnosing the failure require different evidence.

Send MR the complete NTN reference, quantity, equipment identification and bearing position. Include an exploded drawing showing the rings and adjacent parts. If some marking is missing, add clearly labelled measurements and readable photographs, stating which components remain in the machine.