• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

Cobra rear disc issues.


alexp11

09/2014 MTOTM Winner
MTOTM Winner
Joined
Jul 20, 2013
Messages
68
Reaction score
0
Points
0
Age
29
Vehicle Year
1993
Make / Model
Ford
Transmission
Manual
Doing the cobra rear swap on my truck. In the tech library the axle flange seems to sit in the backing plate. However the back of my backing plate is flat so it sits behind the flange. Is this normal?
the next two images are from the article. My cut looks like he one pictured. But the installed picture seems like a much different cut. Either way my plate isn't recessed to sit with the flange.
 


don4331

Well-Known Member
V8 Engine Swap
Joined
Sep 6, 2013
Messages
2,019
Reaction score
1,342
Points
113
Location
Calgary, AB
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Engine Size
5.3
Transmission
Automatic
Alex:

Just finished this conversion on my daughter's '98 on weekend; but didn't take any pictures (yet)...

What you are doing looks right on track so far. Plate is inboard of the axle flange. Picture 2 down from one you inserted from the tech forum shows the line up.

I was anal, at my wife's insistence, and welded the chunk I removed back after I had installed the plate. (Something about if Ford had though only 3 bolts were necessary they wouldn't have added a fourth.)

Here's a couple option/ideas for you: Soft lines are required to calipers on Mustang for suspension; but Ranger has soft line in middle of truck. Therefore, Ranger doesn't need soft lines at caliper. So, I removed them from calipers. I got a pair of BrakeQuip BQ60 banjo fittings.

http://www.brakequip.com/products/automotive-fittings/banjo-unions-adapters

My existing lines fit right into the 3/8″ x 24NF threads (ok, I shortened and re-flared the lines once I knew everything fit), and the 10mm bolt fit right into caliper and it looks like it was designed by Ford...

Then I pulled the parking brake cables out and measured the difference between the drum brakes cable pull and the disc brake (was ~85mm or 3-3/8" for the '98 which had the 9" drums). I took the cables to a local garage door shop and we cut the existing cable ends off, pulled the drum brake spring off, and swaged a couple cable ends on (1st try without removing the plastic covering resulted in the stop pulling off). Much better solution IMHO than some copper pipe...

1st couple stops weren't great, there was some rust on the discs, but now she stops just great.

Don

Standard disclaimer: You're messing with your brakes be careful, know what you are doing, etc, etc.
 

don4331

Well-Known Member
V8 Engine Swap
Joined
Sep 6, 2013
Messages
2,019
Reaction score
1,342
Points
113
Location
Calgary, AB
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Engine Size
5.3
Transmission
Automatic
Alex:

In keeping with anal: I replaced the seals while I had axle out, as I didn't want to do it again in a couple months.

Don
 

alexp11

09/2014 MTOTM Winner
MTOTM Winner
Joined
Jul 20, 2013
Messages
68
Reaction score
0
Points
0
Age
29
Vehicle Year
1993
Make / Model
Ford
Transmission
Manual
Maybe it's not flush and I'm just thinking it because how the colors blend. Anyway. Someone should add a picture of the other bracket in the tech library so nobody else does what I did.

Made the cut upside down...
 

alexp11

09/2014 MTOTM Winner
MTOTM Winner
Joined
Jul 20, 2013
Messages
68
Reaction score
0
Points
0
Age
29
Vehicle Year
1993
Make / Model
Ford
Transmission
Manual
I didn't even see your responses until now. Running a beta system is buggy thanks for the input.
 

JoshT

Well-Known Member
Supporting Member
V8 Engine Swap
TRS Banner 2012-2015
Joined
Aug 6, 2007
Messages
3,820
Reaction score
1,641
Points
113
Location
Macon/Fort Valley, GA
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Transmission
Automatic
2WD / 4WD
4WD
Here's a couple option/ideas for you: Soft lines are required to calipers on Mustang for suspension; but Ranger has soft line in middle of truck. Therefore, Ranger doesn't need soft lines at caliper. So, I removed them from calipers.
Take you wife's advice on this one, Ford did it that way for a reason. You are partially right, because soft lines are needed because of the suspension and that is why a Ranger has a soft line from the frame to the axle. That said soft lines are also needed because of the type of brake. Hard lines to the drum brakes on a Ranger rear axle works because the wheel cylinders are mounted in a fixed location. Unfortunately Mustang (and Explorer) disk brake calipers don't work the same, the caliper is not mounted in a fixed position. The caliper actually floats back and fourth on the mount bracket's pins, and it needs a flex hose at the caliper to accommodate this motion. Might take a while, but those hard lines attached to the caliper will cause a brake failure. It could be rotor failing because it's being flexed each time the brakes are applied, it could be from a fitting working loose because there is no other source flex in that section of the system, or it might be from the hard line failing because your are expecting it to do the work of a soft line.

If you don't believe me, take a look at existing Ford designs. 2010-2011 Rangers came with rear disk brakes, they have a soft line from frame to axle and from axle hardline to each caliper. 95-2002 Explorers came with solid axle and disk brakes, they have a soft line from frame to axle and from axle to each caliper. F-150 solid axle and disk breaks, soft lines are the same. F-250 with rear disks, same. F-350 with rear disks, same. Expedition with rear disks, same. Excursion with rear disks, same. E-series with rear disks, you guessed it, the same.

The sad truth is that the (probably worn out) drum breaks you were replacing, they were safer than the disk brake system that you installed because of the fact that you did not put soft lines at the caliper.

I'm not meaning to be an ass here, I just hate it when people give out bad advice especially where safety is concerned. With you being anal, you daughter's safety at stake, and your own "standard disclaimer" taken into account, you might want to see about getting some soft lines on that truck.

Maybe it's not flush and I'm just thinking it because how the colors blend.
I think that's probably the case. It doesn't really look recessed to me.

I didn't even see your responses until now. Running a beta system is buggy thanks for the input.
Beta? What system are you running, PMs are accepted if you don't want to post here.
 
Last edited:

don4331

Well-Known Member
V8 Engine Swap
Joined
Sep 6, 2013
Messages
2,019
Reaction score
1,342
Points
113
Location
Calgary, AB
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Engine Size
5.3
Transmission
Automatic
JoshT:

Thank you very much.

I complete forgot the caliper float when I was setting this up - damn.

I need to get the soft lines back in - didn't throw them away yet, so just a few minutes work to re-install them and bleed the brakes again.

Apologies to all for my mistaken advice.

Don't do what I did; keep the soft lines.

Don
 

JoshT

Well-Known Member
Supporting Member
V8 Engine Swap
TRS Banner 2012-2015
Joined
Aug 6, 2007
Messages
3,820
Reaction score
1,641
Points
113
Location
Macon/Fort Valley, GA
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Transmission
Automatic
2WD / 4WD
4WD
Don't sweat it man, we're here to learn right? I'm just grateful that you took my post the way I meant it rather than the way it reads. It was 2:30 am local time and I had just gotten home from work, I get wordy and rude when I get tired and often times don't realize it till the next day.

Other than that little bit your advice is actually pretty good. I never would have though about having getting a garage door installer to re-swedge the cable ends, and it does sound like a better option than the copper pipe. I also agree that you wife was a little over cautious about the 4th bolt, but it certainly didn't hurt anything to put it back in there.
 

don4331

Well-Known Member
V8 Engine Swap
Joined
Sep 6, 2013
Messages
2,019
Reaction score
1,342
Points
113
Location
Calgary, AB
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Engine Size
5.3
Transmission
Automatic
Josh:

Last thing I want to do is put bad advice on internet and have it spread... Better to be a hurt some feelings (by the way mine weren't) than have someone get really hurt. Now, if I could only find where I got the idea to fix that site too...

Which why on towing, I have kept my mouth shut about a few of the stupid things I have done historically.

Alexp11:

If you cut the top side rather than the bottom (can't tell for sure from your picture); you probably want to go back and get another bracket to do it right. Most of the force is on top side and cast iron is much stronger in compression than in tension.
 

alexp11

09/2014 MTOTM Winner
MTOTM Winner
Joined
Jul 20, 2013
Messages
68
Reaction score
0
Points
0
Age
29
Vehicle Year
1993
Make / Model
Ford
Transmission
Manual
That's what happened and kinda what I was thinking. Guessing a junk yard is the only place to source single brackets? It's the same on all Cobras 94-04 right? And what did the garage door shop charge you to swagre the cables?
 

don4331

Well-Known Member
V8 Engine Swap
Joined
Sep 6, 2013
Messages
2,019
Reaction score
1,342
Points
113
Location
Calgary, AB
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Engine Size
5.3
Transmission
Automatic
I 'sourced' my brackets from 'auto recycler' in 1st place. :)

Any '94-'04 axle bracket works as I understand it (and worked for me). The difference between the V-6/GT and the Cobra is in the caliper.
 

alexp11

09/2014 MTOTM Winner
MTOTM Winner
Joined
Jul 20, 2013
Messages
68
Reaction score
0
Points
0
Age
29
Vehicle Year
1993
Make / Model
Ford
Transmission
Manual
Last edited:

Sponsored Ad


Sponsored Ad

Members online

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Truck of The Month


Shran
April Truck of The Month

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store


Sponsored Ad


Sponsored Ad

Sponsored Ad


Amazon Deals

Top