Changing bolt pattern

[FORDification]

Calvin, thanks for the link. Yeah, that's what all the other info I've got (and found) also says, so I'm gonna guess that they guy I talked to did use the the '72 Galaxie rotor but just told me wrong on the bolt pattern. I suppose the way to check would be to hit a parts store and see if the '72 Galaxie rotor uses the same inner and outer bearings as the truck rotor. If so, that's the one.

Just to throw this out there for general knowledge, here's a conversion chart for commonly used wheel bolt patterns:

Bolt Pattern Conversion Table
Inches.........Millimeters
4 x 3.93.......4 x 100
4 x 4.25.......4 x 107.95
4 x 4.33.......4 x 110
4 x 4.50.......4 x 114.3
4 x 5.12.......4 x 130
4 x 5.51.......4 x 140
5 x 4.00.......5 x 100
5 x 4.25.......5 x 107.95
5 x 4.50.......5 x 114.3
5 x 4.53.......5 x 115
5 x 4.72.......5 x 120
5 x 4.75.......5 x 120.65
5 x 5.00.......5 x 127
5 x 5.12.......5 x 130

[NATHANHASNORIDE]

Thanks keith ur chart of bolt pattern in inches and millimeters is very helpful

[calvinstoy]

Keith, why couldn't I just get bearings that are the correct ID for the spindle and correct OD for the hub from a bearing rep. such as Timken? By the way Calvin is my father in law, its his truck, his dad bought it new in '72, when he passed it went to his brother, then we he passed a year ago it went to him. He wanted to hot rod it but had no clue how, thats were I come in. He wants to leave it to my son (currently 4 years old), so I have some interest in it + I like a challenge. Thanks, for everybodys input. Mike

[FORDification]

Well, that would probably work, the only thing you might need to watch out for is any dimensional differences between the '72-older and the '73-up Galaxie rotors. While you might be able to find a bearing that will allow you to bolt up the rotor, the rotor must also be capable of receiving the caliper....so if the rotor size changed too, you're gonna run into problems.

Definitely keep us informed on this conversion. I'd be very interested in hearing how it turns out and what you find out.

[calvinstoy]

I'll try to take pics when I do it and I'll keep ya posted. I have done weird things with brakes before just not on a truck and not a drum to disc conversion. I put together my own big disc and caliper combination back in the early 90's on a german hot rod I had, I needed alot more stopping power for autocrossing.

[calvinstoy]

I think i figured it out. If you have already done the disk brake swap with a mid 70's spindle assy. you can use up to a 1972 Galaxie Rotor on your spindle, which should swap you to a 5x4.5" bolt pattern with an 11" rotor, if you want to run a 12" with a 5x4.5 rotor you can use the 72 Thunderbird rotor. If you wat to run a 11" rotor with a 5x5 bolt pattern use the 73 galaxie rotor. They all use the same inner and outer bearings and should use the caliper pad combo from the truck. All the bearings were looked up using Advance auto parts search with mulitiple vehicles. I still need to aquire the spindle assy. from the mid 76's ford truck so I have not purchaced a rotor to try it but I can not see why it would not work. Sources, well of course some info came from here.
http://www.fordmuscle.com/archives/2004 ... ndex.shtml
http://www.roddingroundtable.com/tech/a ... ltpat.html

[fordfanatic]

My question to that is? How are you going to go to a twelve inch rotor without relocating the caliper? If our rotors are 11 in. with stock spindle and caliper alignment, you can't just throw a t-bird rotor on there without it rubbing.(if you were even able to mount the caliper at all.)

[willowbilly3]

The 97 and later metric wheels do not fit the 96 and earlier 5.5 on 5. Possibly the T-bird and Lincoln rotors might swap over for the 5 on 5 pattern. Also then you could get a lincoln disc brake rear end from a 79 or earlier Mark IV ot V. I heard some town cars had the 9 inch disc brake rear too. The Aerostar has the smaller 4.5 pattern.

[fordfanatic]

Calvin's toy, I found it today by mistake, see my post on 4 wheel disc brakes.

[rjewkes]

question why can't i just get a 73 5.5x5 disk setup and masty cylinder and bolt it on is it the spindle problem?

[Randy Beck]

I saw some wheel adapters on the AIM web site that converts the 5X5.5 to 5X4.5

[pat67shorty]

Main thing is you can get 2 new rotors for the price of one adaptor.

The '70 LTD I pulled my 390 out of had new front brakes on it... Damnit. I wish I would have pulled them off before it left... Hindsight is 20/20...

[doc]

So, to get the 5x5 pattern on the front w/o redrilling, I need a '73 Galaxie rotor on my swapped in '78 F-150 spindles, everything else as is.

Correct?

I have a set of NOS new-in-the-box 15x8.5 Appliance slots in the 5x5 pattern I'd love to use.

Thanks!
Doc

[fordman]

what happened to your 78 f 150 rotors and hubs? they should be the same 5.5

[doc]

I have the 5x5.5....I want/need 5x5 pattern....

Thanks!