Explorer to Aviator front brake upgrade

[firefly1246]

just wondering if there is any height difference between our knuckles and the aviator ones. out of curiosity

No height difference between the two knuckles. Just a larger dust shield and the caliper bolt holes are in different location for the larger calipers.

 

[firefly1246]

Update:

After 20K miles and almost 2 years, these brakes are holding up great. I have pulled a couple 6500lb loads and feel a huge difference in braking power. Not quite like pulling with a super duty but an improvement over stock. I painted the calipers silver with G2 caliper paint which is holding up nicely.

 

[Fredness]

Looks like this will work on the front of my 2005 Sport Trac, but not the rear - you guys all have the IRS 8.8 and not the solid axle, right?

 

[87350gta]

Looks like this will work on the front of my 2005 Sport Trac, but not the rear - you guys all have the IRS 8.8 and not the solid axle, right?

Correct, all 2002 and newer non-sport explorers have irs.

 

[Fredness]

No info on an IRS swap to a Sport Trac, so fronts will work until I can fab brackets...
Great info - upgraded to cryo slot rotors and Hawk LTS pads awhile back and need more now that we have a travel trailer!

 

[firefly1246]

Looks like this will work on the front of my 2005 Sport Trac, but not the rear - you guys all have the IRS 8.8 and not the solid axle, right?

The sport trac is based on the 2nd generation explorer and has a slightly different front end than the 3rd generation explore. So from this point forward in my post i will refer to the 2nd gen explorer and 1st gen sport trac as a 2nd gen. I don't know of anyone who has fit aviator front brakes to a 2nd gen. The offsets of where the brake is relative to the wheel is about an 1" different between the 2nd and 3rd gen.

Good luck if you decide to go down this route, let us know how it turns out. When I get some free time I will try and take some measurements, as i have both a sport trac and a 3rd gen.

Update:

So, I did some online digging as this got me curious:

1st gen Sport Trac and 3rd gen explorer use the same caliper.

When comparing a 2nd gen and 3rd gen rotors they are similar, but with some key differences:

Sport Trac / 3rd Gen / Aviator
OD: 12.01"/12.01"/12.99"
Height: 2.61"/2.22"/2.29"
Nom Thick:1.02"/1.02"/1.1"
Hub Size: 2.83"/3.23"/3.21"
Bolt Circle: same 5x4.5"
Weight: 19.25#/19.25#/23#

The 3rd gen and 2nd gen have the same size rotors, with 2 main differences: the 2nd gen rotor is 0.41" farther apart from the hub to outside of rotor, so the rotors will not be in the same spot. The dia of the hub is also different.

In order to successfully install aviator front brakes on a 2nd gen explorer/1st gen ST the following would need to occur:

1) Swap aviator front hubs to a 2nd gen knuckle in order to have correct hub diameter. This would only potentially work on a 4wd 2nd generation as the 2wd 2nd gen using a totally different knuckle/hub. I don't know if this would fit on the knuckle.
2) The bolt pattern for the aviator front brake caliper is different then the 2nd/3rd gen explorer, so a bracket would need to be fabricated.

or if 3rd gen knuckles could be used on a 2nd gen then it would be a much easier swap. Both use the exact same lower ball joints and tie rod end, but use a different upper ball joint. Another question would be where everything is in relation to each other. After looking at some pictures they look really similar, the 2nd gen is iron and 3rd gen is aluminum. On the 4wd models both use a 27 spline axle.

This is all assuming one would have at least a 17" wheel, as the aviator doesn't fit under a stock 16" 2nd gen wheel even with the greater offset.

Man after doing this research this has really got me thinking... and I have parts just sitting around to be able to check it. Looks like a new project might be in order.

 

[Fredness]

Nice! I got some time as I have to fix the rear brakes first...

 

[87350gta]

You could check and see if the press in 3rd gen upper ball joint has the same o.d. as the 2nd gen. Maybe press a 3 rd gen into the upper arm of the 2nd gen.

 

[firefly1246]

You could check and see if the press in 3rd gen upper ball joint has the same o.d. as the 2nd gen. Maybe press a 3 rd gen into the upper arm of the 2nd gen.

That is exactly what I was thinking. I am going to take some measurements this evening after work.

 

[87350gta]

I just did some quick checking. The 02-05 looks too small, but the 06-10 upper looks close. You might have to change your front half shafts also. The newer ones might be longer overall.

 

[firefly1246]

So I took some measurements of the two assemblies:

Aviator
ball joint 1.695"od
Knuckle
Overhaul height 18.125"
Lower balljoint to hub height 5"
Lower balljoint to steering 3.875"
Lower balljoint to full clock 3.75" front
Lower balljoint to upper balljoint 3.5" thick
Lower balljoint to hub 4.5"
Lower balljoint to wheel mount 4.75"

Sport Trac
ball joint 2.000" or 1.900 OD
Knuckle
Overhaul height 14.5"
Lower balljoint to hub height 5"
Lower balljoint to steering 4.5"
Lower balljoint to full clock 3.75" back
Lower balljoint to upper balljoint 3" thick
Lower balljoint to wheel mount 4.5" thick

So.... the 3rd gen balljoints definetly won't press fit into the 2nd gen upper A arm. The 2nd gen are 2.00" (i also found some aftermarket ones at 1.9") and the 3rd gen are 1.675"(including some surface rust). Might need to look at F-150, 4th gen, etc and see if there is another alternative.
Most things are in the about in the correct spot relative to one another. The hard stop for a full clock are on opposite sides of the knuckle, but the 3rd gen knuckle has material in the correct spot to stop the turn. The overhaul height is a concern as well as the 3rd gen knuckle is 18.125" plus about 1.5" for the ball joint boot area and the 2nd gen is 14.5" plus 1". That is a 4.125" difference in overall height. I have a 2" TT, which would put the upper A-arm at 2.125" above the normal height.

Update:

The 97-03 F-150" Upper Balljoint is 2.00" or 1.90" and has a taper fitting that goes into the knuckle like the 3rd gen. I will just need to check the size of the taper fitting vs a 3rd gen balljoint

 

[boominXplorer]

They wouldn't work without dropping the lower control arms the 4" difference between spindles. The angles of everything would be way out of wack as the suspension travels. I think it would be way closer to swap in place for a 4" superlifted truck than a stock truck.

 

[firefly1246]

So I did more measuring and whipped out some trigonometry.

Went to Advance Auto and measured a F-150 Moog Ball Joint, and the taper is a bit bigger than the 3rd gen upper ball joint.

F-150 Moog Ball Joint K80014:
1.900" Press Fit
Taper Section tapers from .7690" to .629" over .861" or 10 degree taper
M14x1.5 Threaded section
Balljoint can bend up to 45 degrees from center, 90 degrees total motion.

I also have compared the angle and amount the A-arm would need to be adjusted from the frame.

The A-arm is 10" from the center of bushing to the center of the ball joint and difference in knuckle height is 3.625" (my original calculation in overall height was wrong). Since I have a 2" TT the overall upper A Arm will move up 1.625".

The below calculations assumes one has already done a 2" TT (like I have):

A arm would be 9.22 degrees up from stock and the A-arm would need to move toward outside of vehicle .133". Then minus 0.500" due to difference in location of upper and lower balljoint from 2nd to 3rd gen. would make you need to move the A-arm .367" toward the center of the vehicle.

If you then compare this to doing a 2" TT: The A-arm is 11.3 degrees lower than stock and the A-arm has to move .210" toward the center of the vehicle. I already have a 2" TT and therefore my A-arm is already .210" toward center of vehicle. Therefore the A-arm would only need to move another .367"-.210" = 0.157" toward center of vehicle.

If one did a 3" TT, the angle would be 16.6 deg and the A-arm would need to move .460". Since i know people have done 3" TT, I am pretty sure it should be able to move the .367".
However: If one has not done a TT then the A-arm would need to move .180" toward outside of vehicle and the angle would be 19.9 degrees.

In conclusion, the overall height of the 3rd gen knuckle should not pose an issue from a geometry concern. On the other hand still would need to find a upper balljoint that would work. Or one could ream the taper on the 3rd gen knuckle deeper to use an F-150 balljoint.

Hope you enjoy all those numbers
-Scott

 

[87350gta]

Did you ever check the 06-10 explorer upper ball joint?

 

[firefly1246]

Did you ever check the 06-10 explorer upper ball joint?

No, advance auto didn't have one. I believe most of them must just replace the whole upper A-arm. It also looks like the part that presses into a arm is not tall enough by the photos. Anyone out there able to measure their 06-10 explorer upper ball joint?

 

[rewind1]

@firefly1246 , Thanks for the idea and the write up.

I just went to the junk yard and got the whole setup for $120 total. That includes the knuckles, calipers, caliper brackets, pads, rotors and I think even the hubs. (edit:yup,hubs too!)

I had planned to replace my upper control arms in the coming weeks. To hell with scope creep! This will be a huge upgrade and for very little money.

If time allows, I will do some testing with fresh pads on the original rotor before the swap and equivalent pads on the aviator rotors after for comparison.
I am on 31s so I expect the times/distances to be a bit higher than the factory numbers but should provide a good picture of the improvement.

 

[06bluez]

just an FYI, this swap works great on 4th gens also, see this thread:

Front brake upgrade

 

[boominXplorer]

Just want to bump this thread to see if anyone has managed to fit them under an offset 16" wheel? I'm running ranger wheels on the wifes 04 Explorer and want to upgrade brakes.

I test fitted a wheel on the knuckle and it almost sat down flush, was probably 10 mm of less from seating. It hits the very front of the caliper (pushed all the way forward as if pads were worn down) and just the edge of the dust shield by the tie rod. It looks like a little trimming and a very small spacer and they will work.

17" wheels is not the answer I'm looking for. I already have 5 265/75r16 Goodyear Duratracs on the truck now and with the ranger wheels it sits perfect.

 

[Number4]

Will grinding some of the caliper off help?

 

[boominXplorer]

It's not even close to fitting past the drop center area of the wheel so grinding the caliper won't help. Judging by the steel 2nd gen (same offset she is running) spare I have, a small wheel spacer will keep the caliper off the wheel. I need to pull one of her aluminum 16s off to see if it's similar in fitment.