The 1970 Oldsmobile Chassis Service Manual specifies Low Range Springs for the right side of the car and High Range Springs for the left side of the car. Can high range and low range springs still be purchased and what is the difference between the two?

 

I haven't seen anything listed as such, just detailed specs for each spring part number as shown below. I suppose you could mix springs to give you the Low Range and High Range (whatever that means). I would say don't worry about that and just get a matched set of springs.

> 5390 small block - no AC
> wire diameter = 0.650"
> load height = 11.000"
> load = 1952 pounds
> rate per inch = 336 pounds
> free height = 16.808"
>
> 5382 big block - no AC, small block - AC
> wire diameter = 0.660"
> load height = 11.000"
> load = 2066 pounds
> rate per inch = 360 pounds
> free height = 16.724"
>
> 5400 big block - AC
> wire diameter = 0.660"
> load height = 11.000"
> load = 2167 pounds
> rate per inch = 360 pounds
> free height = 17.004"
>
> 5536 442 small block - AC - heavy duty, 442 big block - no AC - heavy duty
> wire diameter = 0.690"
> load height = 11.000"
> load = 1984 pounds
> rate per inch = 488 pounds
> free height = 15.063"
>
> 5450 small block - AC - heavy duty, big block - no AC - heavy duty, -442 big block - AC - heavy duty
> wire diameter = 0.690"
> load height = 12.000"
> load = 1642 pounds
> rate per inch = 454 pounds
> free height = 15.616"

 

Production springs have a spring rate tolerance, plus/minus a few pounds per inch. I suspect that on the assembly line, Olds used the high range springs (those at the upper end of the tolerance) on the driver's side, since the car was more likely to be driven with only a driver. Replacement and aftermarket springs are not rated this way and unless you test them, there's no way to know. I wouldn't worry about it.