Drilling late model rotors to fit early model hubs

[bj461a]

Has anyone tried this ? I am finding out the difficulties of obtaining the correct early model rotors for my front disc conversion. I have early model mini truck parts, and need 6 hole rotors that bolt to the hub, with wheel lugs only pressed through the hub.
If late model rotors have the same offset, etc, I should be able to drill the needed 4 mounting bolt holes to bolt onto my early model hubs.

Anyone tried this ? Safety concerns ?

I have ran into the same hassle as many trying to obtian the correct rotors.


Guess I could get diff hubs but I'd rather not.

 

[John Smith]

Has anyone tried this ? I am finding out the difficulties of obtaining the correct early model rotors for my front disc conversion. I have early model mini truck parts, and need 6 hole rotors that bolt to the hub, with wheel lugs only pressed through the hub.
If late model rotors have the same offset, etc, I should be able to drill the needed 4 mounting bolt holes to bolt onto my early model hubs.

Anyone tried this ? Safety concerns ?

I have ran into the same hassle as many trying to obtian the correct rotors.


Guess I could get diff hubs but I'd rather not.

I actually prefer the style you have even though the rotors can be more expensive. The ease of swapping the rotors is worth it IMHO. Not sure why you are having trouble finding the correct rotors. Rockauto should have them as do these folks. ALL-FOREIGN CAR PARTS - Import & Domestic Car Parts, Import & Domestic Truck Parts, Brakes, Rotors, Distrubutors

To answer your original question I would not modify your rotors. If you want the kind that use the press in lug studs sell yours and buy a set of later hubs.

 

[YotaJosh]

I had the same early hub problem, and didn't want to pay the premium for the special rotors, so I drilled some late ones to fit.

Axle has been apart several times since, and I've checked them for any issues. None so far.

 

[crushr]

Yeah, they are really elusive. SOR, Cool Cruisers, and Man a Fre carry them. Kragen/Checker/Schucks used to carry them, DNK if they still do.

 

[grant5127]

Or.....

Replace the old style lug studs with the later, longer, larger shoulder, and re-drill the hub holes.........

 

[bj461a]

Redrilling the hubs so that the longer wheel studs is an option.

I can't see a issue with that.

It has also been suggested to me to bush the stud holes to the size of the mounting bolts, and assemble using bolts with larger dia washers.

Sounds liek I'll be on my lathe tonight.

No matter, I have the new style rotors and will use them.

 

[Vicm]

Why not get the newer hubs.
That was what I did.

 

[edwjmcgrath]

Update on this problem and a possible solution

I too was looking for 6 hole rotors to go on the earlier hubs. They are getting more and more rare and more and more expensive. As another person noted, some places say that they have them, but then it turns out that they are the 8 hole rotors. MAF can get them but they talked me out of ordering them because they don't fit right. The only sources I could find are Toyota OEM and CCOT (which is my source of last resort). These ranged from $200-$280 for the pair compared to under $60/pair for the 8 hole and wide availability.

So...I decided to go with the 8 hole rotors.

I considered sourcing the later hubs or drilling out the rotors but decided to look into the idea of bushing down the existing holes. I measured the existing holes at 15mm and the bolts needed 10mm holes and the thickness of the flange on the rotor is 8.5mm. I found these bushings online for under $2 for 6. 15x10mm and 4mm. (I used two per hole and they are a PERFECT fit). I have a bunch of flanged bolts where the flange is 20mm and found some grade 8 lock washers that are 22mm OD. So for about $12 I was able to bolt the 8 hole rotors onto the 6 hole hub. I even had my Mechanical Engineer SIL check it out and got his stamp of approval.

 

[chevyfj40lc]

I have a 74 fj40 whit fj cruiser2008 rear disc brake on my front hub, mine came originally whit drum brakes

 

[edwjmcgrath]

REALLY? What are you using for hubs and calipers?
I would be shocked to find that two vehicles 35 years apart had compatible rotors.
Hub center hole, mounting bolt holes, overall diameter, disk surface...
Here are photos of the 8 hole rotor and the 2008 FJC rotor. They look very different.

 

[dryduststorm]

Update on this problem and a possible solution

I too was looking for 6 hole rotors to go on the earlier hubs. They are getting more and more rare and more and more expensive. As another person noted, some places say that they have them, but then it turns out that they are the 8 hole rotors. MAF can get them but they talked me out of ordering them because they don't fit right. The only sources I could find are Toyota OEM and CCOT (which is my source of last resort). These ranged from $200-$280 for the pair compared to under $60/pair for the 8 hole and wide availability.

So...I decided to go with the 8 hole rotors.

I considered sourcing the later hubs or drilling out the rotors but decided to look into the idea of bushing down the existing holes. I measured the existing holes at 15mm and the bolts needed 10mm holes and the thickness of the flange on the rotor is 8.5mm. I found these bushings online for under $2 for 6. 15x10mm and 4mm. (I used two per hole and they are a PERFECT fit). I have a bunch of flanged bolts where the flange is 20mm and found some grade 8 lock washers that are 22mm OD. So for about $12 I was able to bolt the 8 hole rotors onto the 6 hole hub. I even had my Mechanical Engineer SIL check it out and got his stamp of approval.
View attachment 583749

 

[71-CRUISER]

Correct early rotors are still available from Toyota.

You can also get them from several aftermarket suppliers. Anyone that has a WorldPac account can order the correct Mountain (oem supplier) rotors.

Also Rock Auto has correct rotors for $19 ea

 

[65swb45]

That's one of the problems with dredging up old posts: the world can change a lot in seven years.

I remember a Toyota Trails article from about 2001 called The Myth of the Rare Part.