Vented rotors on a PRE 81 PU

[baxter650]

There are many threads on swapping to vented LC rotors and IFS calipers for the 81 and up first gens but nothing really for the 80 and earlier trucks.
I am sure i could fudge my way through it but i was wondering if there was someone here that had already done it themselves and could shed some insight my way.
I have owned and worked on both front diffs but i must be honest, i couldn't say what the differences are in how the rotors mount.
Anyways if you could tell me what year vented rotors i can use i would be a happy camper.
Thanks Vince.

 

[2ndGenToyotaFan]

As far as I know the rule of thumb is to get rotors from the same year Land Cruiser as year mini truck you are working on, because the knuckles/hubs/brakes evolved at the same time and are the same except the vented vs non-vented rotors. I remember reading that the rotor mounting changed every few years from the late 70's to early 80's....

 

[baxter650]

Well if it's that simple that's perfect, thanks much.
Vince

 

[2ndGenToyotaFan]

I hope it is! You could always report back and let us know what you end up using and how you like it.... Hehehe

 

[BJ_bumperboy]

Toyota Trekker - BIG brakes ?

 

[ferg]

I had to add a hardened washer between the calipers and the moounting ears. Otherwise FJ40 rotors would rub on inner edge of caliper. Cost <$1.00 from hardware store.

 

[YotaJosh]

Early mini truck hubs used 6 bolts to attach the rotor to it, and the wheel studs remained untouched.

Late mini truck hubs used 2 bolts, and all 6 wheel studs pressed through the rotor into the hub.

The late model rotors (2 bolt + 6 stud holes) are cheaper than the early ones, so I've discovered.

You can drill 4 more holes in the cheaper late model rotors to make them bolt on to an early model hub. This is what I did and I've had no problems in 2 years.

As stated above, matching the years between the truck and LC also works since they are the exact same parts.

 

[pappy]

If the issue is how the rotor attaches to the hub, why not also replace the hub? I'll bet the knuckle is the same.

 

[baxter650]

If it is just the hub, then i can just swap my fronts with my rears. The pair on the rear are newer by at least a few years.

 

[Hilux]

According to Napa, the 79-80's have a lower hat than 81's and up.

The 81's and up I know are direct bolt-ons for the FJ60 rotors...

Now... I've measured, and posted it, that I believe the Tacoma rotors will fit OVER the 79-80's after the hub's been machined down.

This CAN NOT be done to the 81 and up's without machining the WMS down.

If I don't have to, I don't want to put press-ons back on it.

I've got some measuring to do...

60 rotor: Store Locator | NAPA Online "Height : 1.89"

Tacoma rotor: Store Locator | NAPA Online "Height : 2.77"


Now I gotta go measure a hub



1.89 - 2.77 = .88

awe, man...

I just found out the 79-80 brake rotors are different from the 81-85's...

Could it be? Napa says the 79-80 rotors are 1.65" And the 85/ Fj60's are 1.89" A difference of .24" A 1/4 of an inch....

Does anybody have, or know if these (hubs) will work? Assuming the calipers are the same, and bolted in the same place, it looks to me like the hubs are 1/4" back...

Also, Marlin mentions something about this in his vented rotors/ IFS calipers upgrade product description...

"This kit also fits 1979-80 axles that have been converted to 1981-85 spindles."

 

[Hilux]

I think I'm finding my brain fart now...

Put Tacoma rotors over a 81-85 hub, and the calipers will not bolt on by the difference in the new rotor face OVER the hub b/c the rotor is not behind the hub anymore.

.266". By my Napa Taco rotor.

Somehow remove 1/4" WMS from 81-85 hubs and machine down the outter diameter of the hub so the rotor will fit over it and you now have floating rotors...

79-80 hubs ALREADY have a 1/4" in difference.


FJ60 rotors are 1.89" high. Same as the 81-85 rotors.

79-80 Hilux rotors are 1.65" high

The calipers share the same bolt pattern so the calipers are a bolt on.

Now, the 79-80 rotors are 1.65" high, so they are NOT direct bolt on's with FJ60 rotors.

The rotor will be .24" too forward.

Now, I've measured the hub thickness and on my 84 it's .80".

Tacoma rotors are 2.77" So .80" - 2.77" = 1.97" Won't work.

Now take 1.65" and sub that with 1.89" and ya get .24"

Now where have I seen .24" before?

 

[2ndGenToyotaFan]

I think I'm finding my brain fart now...

Put Tacoma rotors over a 81-85 hub, and the calipers will not bolt on by the difference in the new rotor face OVER the hub b/c the rotor is not behind the hub anymore.

.266". By my Napa Taco rotor.

Somehow remove 1/4" WMS from 81-85 hubs and machine down the outter diameter of the hub so the rotor will fit over it and you now have floating rotors...

79-80 hubs ALREADY have a 1/4" in difference.


FJ60 rotors are 1.89" high. Same as the 81-85 rotors.

79-80 Hilux rotors are 1.65" high

The calipers share the same bolt pattern so the calipers are a bolt on.

Now, the 79-80 rotors are 1.65" high, so they are NOT direct bolt on's with FJ60 rotors.

The rotor will be .24" too forward.

Now, I've measured the hub thickness and on my 84 it's .80".

Tacoma rotors are 2.77" So .80" - 2.77" = 1.97" Won't work.

Now take 1.65" and sub that with 1.89" and ya get .24"

Now where have I seen .24" before?

Sooooo what you're saying is.... It still wont work?

 

[Hilux]

79-80 hubs will not work with FJ60 rotors...

Now I know dude's not asking about Tacoma rotors, but I thought I'd throw it in there.

It LOOKS like Taco rotors will work if you throw them over 79-80 hubs.

Now we're back to having a better field strip for a Birfield, being able to bolt the spindle on (but maybe not the right way), and being able to remove the rotors WITHOUT having to remove the hub first...

Which I like the idea of b/c it makes even the monumentally hard task of removing the rotors just to have them turned, into an easy as pie replace.

I know it's confusing as ell, but I can't think of a better way to write all that.

 

[GLTHFJ60]

79-80 hubs will not work with FJ60 rotors...

Now I know dude's not asking about Tacoma rotors, but I thought I'd throw it in there.

It LOOKS like Taco rotors will work if you throw them over 79-80 hubs.

Now we're back to having a better field strip for a Birfield, being able to bolt the spindle on (but maybe not the right way), and being able to remove the rotors WITHOUT having to remove the hub first...

Which I like the idea of b/c it makes even the monumentally hard task of removing the rotors just to have them turned, into an easy as pie replace.

I know it's confusing as ell, but I can't think of a better way to write all that.

Funny you should mention that. Seems like Front Range Off-Road has beat you too it. Thread on this just came up in the 60 forum, so it's with the later hubs, but it may work for you guys too.

Front Range Off-Road Fabrication