Switching from 5x5.5 to 5x4.5 lug pattern

[convincor]

Back to the drawing board. The Napa rotors are the same.
Another thing is the offset of the rotor itself in relation to the hub.
The caliper would be hanging out to far off the slides.
So I'm going to keep working on this and see what I can come up with.
I found the rims I want but can't get them 5 on 5-1/2.. So somehow this is going to happen...

[convincor]

update.
if tybob81 got the 83 rotors to bolt on and work there for a 83 with 5000lb GVW as there the same rotors for 73-79, and still 5 on 5-1/2". 80-83 there was a 4600 GVW that used the 5 on 4-1/2" bolt pattern but the bearing spacing is different, (shorter) so you can't tighten the bearings. The outer bearing bottoms out on the radius of the spindle. Also, the diameter of the rotor is only11.04" on the 80-83 4600lb rotors vs 11.72 on the 73-79 truck rotor.. The rotor brake surface is also 3/4" away from the spindle..
I've been going thru the Raybestos site and comparing dimensions on some of the other rotors that use the same bearings as the 73-79 trucks and came up with 2 posability's that are 5 on 4-1/2"
One is for a 72 LTD, the other is 72 Torino with police/Taxi package.
Both these rotors have the same height as the truck rotors, same thickness, same diameter, and use the same bearings. Now the difference is in just one of the dimensions. There calling height.
There's 2 heights listed for each rotor.
for the 73-79 truck it's 7.785 and 5.387
the LTD it's 7.785 and 4.525
And the Torino It's 7.785 and 4.807
The 80-83 4600lb rotors are 7.02 and 4.28
So, I'm thinking that the 72 Torino police/taxi would be the best to try next, but the problem now is that there special order and $149 each...
The LTD rotors are only $94 but still, no one stocks them.....
I'll make a move soon, just wanted to give you an update....
Napa # NB 4885540 Raybestos # 6028R

[KF100TK]

Nice homework , lets say those rotors work ,how could a guy get them drilled and slotted?

[SMF Speed&Custom]

I haven't been keeping up with this thread but here is my link I posted not too long ago... Hope it helps. http://fordtruk.com/forums/viewtopic.ph ... highlight=

[convincor]

Here's the latest.
That Torino rotor won't work either. I've been back a forth with Raybestos and finally got some dimensions and for the most part the rotors are the same with the exception of the bearing spacing. The Torino again is to narrow and the outer bearing will not seat before bottoming out on the spindle. One option would be to machine the spindle shorter but then were stuck buying a $160 rotor that who know's how much longer there going to produce and at what cost..
So, I've been asking around some of the other manufactures to see if the would be willing to make the rotor we need. Still the same rotor we use now which fits 1975 - 1983 E-100 ECONOLINE, 1973 - 1983 F-100 PICKUP, 1975 - 1993 E-150 ECONOLINE, 1975 - 1993 F-150 PICKUP
They even make them in cross drilled and slotted, but they all say they don't do custom anymore as they've been sued...
So this leaves the last option. Buy the regular rotors and have them machined to what I want. I've got a shop locally that is willing to do them.
I would give him 4 to do. 2 for me and 2 for a friend that also wants a pair.
He said he could do them for about $100 each. So with the cost of the stock rotor from Advanced Auto/Parts America being $34. Total cast is still less than the $160 Torino rotor.. And I know that they will fit..
So that's what I'm doing.

[SMF Speed&Custom]

Are you saying the 80's F100 rotor will NOT work?

[convincor]

In short, NO they don't work.
There was 2 different GVW rated F100's in 1980-1983.
5000lb GVW uses the same rotor as 1973-1993 f100 and f150 which is the 5 on 5-1/2".

The 4600lb GVW is what uses the 5 on 4-1/2". It uses the same bearings and seals but WON'T work on the 5000lb spindles.

There is also a 3/4" difference in diameter.

[SMF Speed&Custom]

What if I have on my 66 F100 the 76 F100 Spindles? Then will they fit or no?

[convincor]

no

[SMF Speed&Custom]

Are you sure they wont work? Are you positive? Completely positive? Extra Completely Positive? HAHAHAHA just messing!

[KF100TK]

Dumb question, but why can't the rotors be redrilled like the rear axels?

[fordman]

thinner metal in the rotor facing.

[FORDification]

When you do this, please jot down all the pertinent information on the modifications needed, part numbers, etc., as well as taking some pictures. It would make a great write-up for the site!

[Thunderfoot]

Dumb question, but why can't the rotors be redrilled like the rear axels?

Unless I misunderstood, I think that is what he is going to do. You need to have it done at a machine shop so that it is concentric...


Fordman, the rotor facing is the same thickness all the way so wouldn't change anything there...

I was figuring I would go this rout unless someone found a stock rotor that would work...
Thanks for doing all the work on finding out this info convincor and also looking forwards to how your rotors come out and pictures

[convincor]

Dumb question, but why can't the rotors be redrilled like the rear axels?

read post #50. That's what I'm going to do.

And Yes Keith, I will document with pics.