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Explorer disk brake question

widowmaker77

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Oct 11, 2007
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Have a question for any of you guys that have the done explorer rear disks. I’ve searched around and can’t find any info on this. According to Currie, in order to use the explorer setup i have to install a spacer ring on the axle. They are using the set 20 bearings in the video on their website. My question is do I have to use the set 20 bearings or can I keep the sealed bearings? My inderstanding is in order to use the set20 bearings I also have to change the rear axles as the original axles are a different diameter and won’t accept the set20 bearings. I do want to put new 31 spline axles in eventually and will go to this bearing style but a complete axle and carrier upgrade isn’t in the cards right now. Just trying to see if I can go ahead with the explorer brakes or will I have to wait until I can upgrade the axle shafts.
 

Yeller

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Depends...... Does your current axle have the correct bolt pattern on the axle retainer/bearing cup? Do your axles have the correct spacing from the bearing retainer to face of the axle? If those boxes check yes then it should not be an issue. The Explorer conversions I've done required a spacer to make up for the backing plate for the drum brakes not being there, which I'm assuming is the spacer that you are referencing.
 

Apogee

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The spacer between the axle bearing and the shoulder on the axle is to set the axle offset dimension to the 2.50" Explorer (and big-bearing Torino) spec. While the thickness of the spacer will vary depending on whether you're running SET20 or sealed ball bearings, either setup should work just fine with the sealed ball bearings being slightly simply IMHO since you don't have to account for "crush" of the external oil seal used with the SET20 in order to set the bearing preload correctly when running the ball bearings.

Yeller is referring to the spacers (or billet machined retainers) required to account for the thickness of the backing plates, since a flat retainer plate by itself won't contact the axle bearing and will allow the axles to walk in an out if you don't come up with a way to prevent that.

Tobin
 
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widowmaker77

widowmaker77

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Depends...... Does your current axle have the correct bolt pattern on the axle retainer/bearing cup? Do your axles have the correct spacing from the bearing retainer to face of the axle? If those boxes check yes then it should not be an issue. The Explorer conversions I've done required a spacer to make up for the backing plate for the drum brakes not being there, which I'm assuming is the spacer that you are referencing.
I’m not sure now after reading different threads about the swap. My axle is a stock 77 big bearing. If the bolt pattern isn’t correct then I feel like I should be able to weld the holes up on the explorer backing plate and redrill them to match the rear end bolt pattern.
I’m guess that’s the spacer I’m referencing?? It’s the spacer ring Currie enterprises sells for this conversion.
 

SteveL

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The 77 housing doesn't have the correct ends for the explorer swap. From what I've read you want the "torino" ends.i thinks they come on the 77 bb housing. You can also but the torino ends from the vendors to weld onto your housing. Thes other guys may have a better fix. I've got the caddy disc on my 77 housings.
 

Apogee

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As stated above, you'll need the big-bearing Torino or "new-style" ends to run the Explorer disc brakes as they came on the Explorer, but plenty of people modify them for other housing ends or swap housing ends to make them work. Clearly the 5x4.5 wheel pattern on the rotors needs to be modified to work with our rigs, so the rest depends on the housing, and the '77 EB housings use the "old-style" big-bearing pattern with the 2.38" x 3.50" rectangular pattern and 1/2" retainer bolts. Some folks on here call the "Torino" housing ends a "medium-duty bearing" housing, though it uses the same Ø80mm axle bearing options as all of the big-bearing housings, so I never really understood that description. IIRC, the "new-style" or "Torino" housing ends were only available for 2 years or so in the early 70's, maybe '73 and '74? I'm sure someone here knows better than me and will correct me if I'm wrong.

Aside from the axle housing end pattern and retainer bolt size differences, the axle offsets are different between Torino and old-style ends, hence my post above.
 

DirtDonk

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I could be wrong but I think it was the 74 and 75 model years that got that. Been a while though so I could be wrong too!
 

toddz69

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Nov 28, 2001
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It was '74-'75 when those 'medium duty' rear ends were available. They were known as 'medium duty' because they were offered on the mid-range GVWs in those years and were a combination of the Torino/late model big bearing rear ends combined with the smaller 10" drum brakes from the small bearing rear ends.

Todd Z.
 
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widowmaker77

widowmaker77

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Ok so now I know I will need to modify my explorer backing plate in order for it to bolt up to the 77 housing. What about the spacer rigs that Currie says are required to run the explorer brakes? Will they work with the sealed bearings? If not, will the set 20 bearings fit the stock 28spline axles or are they for different diameter axle shafts? Thanks for any more help on this. I might just go with the riff stuff brackets and Chevy calipers like I did on my sons big bronco when we did the sas swap and went to a nine inch rear
 
Last edited:

destroyer000

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Jun 14, 2013
Messages
49
ive got the explorer disc brake swap on my 74, you need a big bearing housing. the big bearing housing has the same bolt pattern as the explorer brake bracket. and will use 3 of the holes on the explorer caliper bracket. you will need to notch the caliper bracket. the currier space is needed to make up the difference in the factory backing plate to the caliper bracket . your axles will work fine. pretty easy swap. i redrilled explorer rotors 5x5.5 and opened my center up . ive been very happy with the swap .
 

gnsteam

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I've have looked into this mod over the last few months and wasn't sure how to pursue either. I too, have the old big bearing flange with hole pattern of 3.5" x 2.375". I had resolved to just re-install the factory drums as I reassemble the nine inch. However this thread sparked my interest again. In stead of sourcing the parts at a U-Pull It. I was considering this kit from, Quick Performance.
https://www.quickperformance.com/Fo...ke-Kit-With-Shoe-Style-Park-Brake_p_4023.html
A little more expensive but all new parts and you can get the rotors in 5 x 5.5 wheel pattern. I was just sure how I was going to go about making it fit my flange hole pattern.

Today I found this write up about the mod at Pirate 4X4. Which had an addition link to another wright up.
https://www.pirate4x4.com/threads/explorer-disc-brakes-on-early-big-bearing-ford-9.2658690/

So I think I'm going to order the Quick Performance kit, the Currie spacers and give it a go. Has anyone on here purchased the Quick Performance?
 
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