crazybob
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Are the plastic & the metal (Dorman)master cylinders interchangeable? Thanks!
Master Cylinder
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What do you mean? Bore size and fitting type is what determines if it will interchange.
crazybob
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Sorry, I meant can the plastic one be replaced with the metal one? (Just bolt on), Thanks!
DoubleDingo
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As stated, stick with the style the truck came with.
crazybob
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The reservoir sizes front and rear are based on what brakes are on the vehicle and if miss matched could cause issues, unless upgrading the entire system as a package it isn't worth the possible problems or potential safety issues.
Ricko1966
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The plastic reservoir masters are quick take up,designed for use on the low drag calipers. I personally haven't tried mismatching them. I general don't mismatch things anymore. If GM changed 2 items in combination,there's usually a pretty good reason they changed them as a pair. I have read on other forums about people mismatching them and ending up with a pedal that took a second pump to get pressure. You don't always have time for 2 pumps. I've read more but no reason to waste everyone's time.
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There are also non quick take up master cylinders with the plastic reservoir. If you don't want to crawl into the rabbit hole of master cylinder data to find a matching one replace what was on the truck.
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IF your front calipers and rear wheel cylinders are the same as those of a truck that came with an all-metal master, yes, but if they are different, it is not a good idea.
Mike
