brake master cylinder options - 6.2 diesel

[6.2Blazer]

Need to replace the brake master cylinder on my '90 K5 with the 6.2. The parts stores liste 3 different versions:

- w/ F44 heavy duty brake option and under 8,500 GVW
- w/ F44 heavy duty brake option and over 8,500 GVW
- without F44 option

I know the direct replacement would be the last as it does not have the F44 option, but the questions are:

1. Is one of the other options better?
2. Will the others bolt on?

It's a D60 front and 14FF rear with ABS junk removed. All of the above options are within $5 of each other.

 

[nvrenuf]

I'm stupid - what's "F44" - hydroboost?

 

[6.2Blazer]

I'm stupid - what's "F44" - hydroboost?

I'm stupid with you........

 

[Fordum]

F44 option, also known as a "heavy half" or a "big 10", had slightly larger rear brakes, lower factory gear ratio, and about 300lbs or so heavier spring rating.

Basically a 2500ld rear end with stronger rear driveshaft.

I think the rear brakes were 11"X2.75 instead of 11X2.

From what I remember, it was done mainly for smog reasons. If the weight rating was just a little bit higher, they could leave some of the smog stuff off.

 

[Fordum]

The reason that stuck with me, was because it was supposedly similar to what Ford did.
They made the F100 half ton pickup for decades.
Then, came out with the F150, which was also a half ton, just heavier duty.

 

[6.2Blazer]

I've heard of the F44 option in the '88-newer IFS 1/2 ton pickups, with the main piece of interest being the 14SF it came with, but never in a Blazer.

In any case, I went to a different parts place and the only options they had was either a new or rebuilt master for my Blazer. I bought the new one for $50 and initially it appears to be a direct duplicate of the OEM version.