January 22, 2013

There has been some discussion about rear leaf springs, so I thought
I would photograph original springs and replacement springs.

Here is a picture of original springs on a 300B.
You can click the picture to enlarge.

Here are two pictures of original springs on a 300F.
You can click the pictures to enlarge.


You can see the leaves have a center channel or groove,
and the ends of some leaves are sculpted.

If you were to remove springs from the car and flip upside down, you would see:
(Click to enlarge)

Here you can see the groove and the sculpted end.
Sharp eyes may also catch that the top leaf is cracked at the center.



Not all of the original main leaves I looked at are grooved steel, and not all of the ends are sculpted, so there may be no hard and fast rule on original spring appearance.

Pictured below are new springs on a 300L (these are from Eaton Detroit).
New springs will not be grooved steel.


Click here for a short video on springs

Letter Car Springs

Year	Front Suspension	Front Spring Rate	Rear Suspension	Rear Spring Rate
1955	Coils	800 lb/inch	7 leaves, 55” x 2.5”	160 lb per inch
1956	Coils	800 lb/inch	7 leaves, 55” x 2.5”	160 lb per inch
1957	Torsion bar 40” long X 1.01” diameter	165 lb per inch	7 leaves, 58” x 2.5”	135 lb per inch
1958	Torsion bar __” long X 1.11” diameter	170 lb per inch	7 leaves, 60” x 2.5”	135 lb per inch
1959	Torsion bar __” long X __” diameter	170 lb per inch	7 leaves, 60” long x 2.5”	136 lb per inch
1960	Torsion bar 44” long X 1.08” diameter	175 lb per inch	7 leaves, 60” long x 2.5”	135 lb per inch
1961	Torsion bar 44” long X 1.08” diameter	175 lb per inch	7 leaves, 60” long x 2.5”	135 lb per inch
1962	Torsion bar 40” long X 1.01” diameter	130 lb per inch	6 leaves, 57” long x 2.5”	125 lb per inch
1963	Torsion bar 40” long X 1.01” diameter	125 lb per inch	7 leaves, 60” long x 2.5”	125 lb per inch
1964	Torsion bar 40” long X .99” diameter	115 lb per inch	6 leaves, 60” long x 2.5”	95 lb per inch
1964 Ram	Torsion bar 40” long X 1.01” diameter	125 lb per inch	7 leaves, 60” long x 2.5”	125 lb per inch
1965	Torsion bar 47” long X .96” diameter	110 lb/inch	6.5 leaves, 62” long x 2.5”	85 lb per inch

Some reference material mentions the L heavy duty suspension (below)
but this is not verified in the AMA specifications.

1965 heavy duty	Torsion bar 47” long X .96” diameter (.98” dia with AC)	115 lb/inch	6.5(*) leaves, 62” x 2.5” (*) Zinc interleaf	95 lb per inch

Click here for technical information from Eaton Detroit Spring

Click here to order springs from Eaton with Club discount

Click here for more on Torsion Bars

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