C1 Rear Wheel Bearing and Axle Info
.By Tom Parsons
(edited for publication by John Costales,
Frequently the subject of rear axle
bearing replacement arises for 56-62 Corvettes.
It should be pointed out that some
differences do exist when replacing the outer
rear wheel bearings between the 56, 57 and 58-62
Primarily you should first determine the
bearings you currently have prior to purchasing
Without checking you never know what rear
differential is installed in your car.
Over the years there have been a total of
4 (actually 5) axle bearings for C1s.
1) The replacement bearing for a 56
Corvette (55-56 Chevy pass car) is the
RW507EN or RW507ER (507 series).
The RW507ER has a slightly thicker inner
2) The replacement bearing for a 57
Corvette (57 pass car) is RW307R (307
3) The replacement bearing for 58-62
Corvettes is RW607NR (607 series).
All of the above 3 bearings are ball
4)JNR1542 was a roller bearing for 58-62
Corvettes with positraction as well as 58-64
passenger cars with positraction and also
taxicabs and police cars (which may or may not
have had posi). The JNR1542 (roller bearing) has
been long discontinued and is replaced by (3)
above ball bearing RW607NR that shares the same
5) Many years ago, GM listed a
roller bearing for the 55-56 pass car. I
have never seen an aftermarket
replacement part number for that
bearing, but the GM part number was
7451414 (it has LONG since been
Last year, a customer brought me a
pair of (what appeared to be) original
axles from his 55 Nomad for me to
replace the bearings. They had the
roller bearings and the RW507EN or
RW507ER was a direct replacement (first
time for me to actually ever see 55-6
roller axle bearings).
The 507and 307
series are the same thickness,
but the 507 has a smaller
The RW507EN or RW507ER are
the only bearing that will fit A
56 Corvette and 55-56 pass car.