Front brake rotor size???

[ellisjay2]

There are three different size rotors, I was just wanting to know what size mine were on the 86 2500 longbed, before I stopped by parts store and go through trouble to find out, I can take wheel off and just old school measure it but was tring not too for now. I just read a post someone posted with specs on body and parts that showed 11inch rotors for heavy duty model. I 've been tring o find a site that has all original specs on the whole truck front to back, chassis and all. Then I found a set of rotors for $89 bucks a piece!!! Un! Im gonna shop around to see if I can beat that online probably be best.

[MalibuSSwagon]

look it up on rockauto.com, excellent parts catalogs there.

[Keith Seymore]

Originally Posted by ellisjay2

I 've been tring o find a site that has all original specs on the whole truck front to back, chassis and all.

Where did you look?

http://67-72chevytrucks.com/vboard/s...d.php?t=510519

I have the engineering release charts for all GM brake systems starting in about 1969.

The attached link happens to be a scan of the '87 system, which should be the same as your '86. You'll need to know your truck's GVW in order to determine the correct brake system (JB6, JB7, etc).

And you didn't mention 2wd or 4wd.

K

[Keith Seymore]

Originally Posted by ellisjay2

There are three different size rotors, I was just wanting to know what size mine were on the 86 2500 longbed, .

I only see one rotor size across all 4wd 20 series (K20903 & JB6/JD6/JB7/JD7; 6600 or 8600 lb GVW) and it's a 12.5x1.28".

Similarly, I only see one rotor used across all 2wd 20 series (C20903 & JB6/JD6/JB7/JD7; 7200 or 8600 lb GVW) and it is also a 12.5x1.28".

K

[ellisjay2]

Originally Posted by Keith Seymore

Where did you look?

http://67-72chevytrucks.com/vboard/s...d.php?t=510519

I have the engineering release charts for all GM brake systems starting in about 1969.

The attached link happens to be a scan of the '87 system, which should be the same as your '86. You'll need to know your truck's GVW in order to determine the correct brake system (JB6, JB7, etc).

And you didn't mention 2wd or 4wd.

K

GVW 8600/3900 2wd