As I get older I ponder on why certain options/parts were available throughout the history of our GM trucks.
My question is what specifically triggered that an early 70’s ( pre-square design ) C/K-20 rear axle be either a common Eaton HO52/72 or the less common Dana60?
I have a theory that it was due to the choice of the differential selected but I can’t back that up with chapter-n-verse gospel truth.
Since that style Eaton rear axle was introduced in the late 40’s the only traction aiding diff available was Detroits No-Spin.
When GM introduced the new 67~72 model lineup they were making all sorts of ways for driver comfort - like lower ingress and egress heights and smoother ride comfort in the spring rates.
Well, I recall reading an old sales pitch add for these trucks describing that GM now offered two options of traction aiding differentials - one being the tried and true automatic locking system ( being the No-Spin ) and a newer and more refined limited-slip differential ( being Dana’s Powr-Loc clutch pack diff ).
Since there was no clutch type diff offered for the Eatons ( that didn’t happen until the replacement 14-FF Gov-Loc in the squares after 73 ) and GM was pushing driver/passenger comfort so hard they gave an option of a milder traction aid for the remainder of the model run.
Is it that simple ? Was it the P/L limited slip diff option that triggered the Dana rear axle in those few model years?
I recall seeing some GM literature years ago talk’n about the two diff options in the 70~72 C/K-20 trucks.
Anyone got any insight on this question - inquiring minds want to know….
My question is what specifically triggered that an early 70’s ( pre-square design ) C/K-20 rear axle be either a common Eaton HO52/72 or the less common Dana60?
I have a theory that it was due to the choice of the differential selected but I can’t back that up with chapter-n-verse gospel truth.
Since that style Eaton rear axle was introduced in the late 40’s the only traction aiding diff available was Detroits No-Spin.
When GM introduced the new 67~72 model lineup they were making all sorts of ways for driver comfort - like lower ingress and egress heights and smoother ride comfort in the spring rates.
Well, I recall reading an old sales pitch add for these trucks describing that GM now offered two options of traction aiding differentials - one being the tried and true automatic locking system ( being the No-Spin ) and a newer and more refined limited-slip differential ( being Dana’s Powr-Loc clutch pack diff ).
Since there was no clutch type diff offered for the Eatons ( that didn’t happen until the replacement 14-FF Gov-Loc in the squares after 73 ) and GM was pushing driver/passenger comfort so hard they gave an option of a milder traction aid for the remainder of the model run.
Is it that simple ? Was it the P/L limited slip diff option that triggered the Dana rear axle in those few model years?
I recall seeing some GM literature years ago talk’n about the two diff options in the 70~72 C/K-20 trucks.
Anyone got any insight on this question - inquiring minds want to know….
