How To Select Main Bearing

WARNING: This page is about a different car, the 2012 Nissan Pathfinder. However, it is still accessible from the selected car via links, so may be relevant.

When New Cylinder Block and Crankshaft are Used

Apply the main bearing housing grade on the bottom face of the cylinder block to the row in "Main Bearings Selection Table".

Fig 1: Identifying Main Bearing Housing Grade, Bore Grade And Lot Label
Courtesy of NISSAN NORTH AMERICA, INC.
Apply the journal diameter grade on the crankshaft front to the column in "Main Bearings Selection Table".

Fig 2: Identifying Journal And Pin Diameter Grade On Crankshaft
Courtesy of NISSAN NORTH AMERICA, INC.
Read the symbol at the cross point of the selected row and column in the "Main Bearings Selection Table".
CAUTION:
- Initial clearance for No. 1, 5 journal and No. 2, 3, 4 journal is different. Use two different selection lists for each part.
- No. 1, 5 journal and No. 2, 3, 4 journal have the same signs but different measures. Do not confuse them.
Apply the symbol to the "Main Bearings Grade Table" to select.
NOTE:
- Grade list applies to all journals.
- Service parts are available as a set of both upper and lower.

When Cylinder Block and Crankshaft are Reused

Measure the inside diameter of the cylinder block main bearings housing and the outside diameter of the crankshaft journal.
Apply measurement in above step 1 to "Main Bearings Selection Table".
The following steps are same as in "When New Cylinder Block and Crankshaft are Used".

Main Bearings Selection Table (No. 1 and No. 5 journal)

Fig 3: Main Bearings Selection Chart (No. 1 And No. 5 Journal)

Courtesy of NISSAN NORTH AMERICA, INC.

Main Bearings Selection Table (No. 2, 3 and 4 journal)

Fig 4: Main Bearings Selection Chart (No. 2, 3 And 4 Journal)

Courtesy of NISSAN NORTH AMERICA, INC.

MAIN BEARINGS GRADE CHART (ALL JOURNALS)

Unit: mm (in)

Grade number⁽¹⁾

UPR/LWR

Thickness

Identification color

Remarks

2.483 - 2.486 (0.0978 - 0.0979)

Black

Grade is the same for upper and lower bearings.

2.486 - 2.489 (0.0979 - 0.0980)

Brown

2.489 - 2.492 (0.0980 - 0.0981)

Green

2.492 - 2.495 (0.0981 - 0.0982)

Yellow

2.495 - 2.498 (0.0982 - 0.0983)

Blue

2.498 - 2.501 (0.0983 - 0.0985)

Pink

2.501 - 2.504 (0.0985 - 0.0986)

Purple

2.504 - 2.507 (0.0986 - 0.0987)

White

2.507 - 2.510 (0.0987 - 0.0988)

Red

UPR

2.483 - 2.486 (0.0978 - 0.0979)

Black

Grade and color are different for upper and lower bearings.

LWR

2.486 - 2.489 (0.0979 - 0.0980)

Brown

UPR

2.486 - 2.489 (0.0979 - 0.0980)

Brown

LWR

2.489 - 2.492 (0.0980 - 0.0981)

Green

UPR

2.489 - 2.492 (0.0980 - 0.0981)

Green

LWR

2.492 - 2.495 (0.0981 - 0.0982)

Yellow

UPR

2.492 - 2.495 (0.0981 - 0.0982)

Yellow

LWR

2.495 - 2.498 (0.0982 - 0.0983)

Blue

UPR

2.495 - 2.498 (0.0982 - 0.0983)

Blue

LWR

2.498 - 2.501 (0.0983 - 0.0985)

Pink

UPR

2.498 - 2.501 (0.0983 - 0.0985)

Pink

LWR

2.501 - 2.504 (0.0985 - 0.0986)

Purple

UPR

2.501 - 2.504 (0.0985 - 0.0986)

Purple

LWR

2.504 - 2.507 (0.0986 - 0.0987)

White

UPR

2.504 - 2.507 (0.0986 - 0.0987)

White

LWR

2.507 - 2.510 (0.0987 - 0.0988)

Red

⁽¹⁾	Always check with the Parts Department for the latest parts information.

Use Undersize Bearing Usage Guide

Use undersize (US) bearing when the oil clearance with standard size main bearing is not within specification.
When using undersize (US) bearing, measure the inside diameter of the bearing installed and grind the journal until the oil clearance falls within specification.
Bearing undersize table

Unit: mm (in)
Undersize	Thickness
0.25 (0.0098)	2.618 - 2.626 (0.1031 - 0.1034)

CAUTION: Do not damage fillet R when grinding crankshaft journal in order to use undersized bearing (All journals).

Fillet R: 1.5 - 1.7 mm (0.059 - 0.067 in)

Fig 5: Identifying Fillet R Part (All Journal And Pins) Of Bearing

Courtesy of NISSAN NORTH AMERICA, INC.