What Have You Done To Your Explorer ST Today

[bosephbarking]

My reply was a bit more redneck. lol
I was gonna say when the oem bushings deflect as the diff moves up and down the new bolt is gonna whack the subframe and break the aluminum diff cover.

Which ironically is exactly how it breaks the OEM bolt. The recall documents really do the best job at describing the issue.

"The joint design is not robust to peak axle input torques and manufacturing variability. The primary contributor is insufficient bearing area for maximum joint loads. This results in bearing area deformation, increasing bending stress on the bolt, which may lead to a fatigue failure."

@JCR ST
Putting a bolt directly against metal will ensure it will bend then break. The OEM bolt deflects so much in the bushing it deforms the bushing till it hits metal and bends. What the heck do you think metal on metal will do, take that bolt out. It is a ticking time bomb.

 

[TMac]

My reply was a bit more redneck. lol
I was gonna say when the oem bushings deflect as the diff moves up and down the new bolt is gonna whack the subframe and break the aluminum diff cover.

Well, we're both right. You do have a way with words! Let me point out that the longer bolt will likely be hitting the subframe before the original bushing does much deflecting- therein lies the problem.

 

[UNBROKEN]

Well, we're both right. You do have a way with words! Let me point out that the longer bolt will likely be hitting the subframe before the original bushing does much deflecting- therein lies the problem.

Yup…leaving 1/8” around the new bolt accomplished nothing. That bolt is still gonna whack the subframe.

 

[JCR ST]

Guys, there is no metal on metal. The bolt is 5" long but the sub-frame is only 5/8" from the diff cover and the sub-frame is about 3" thick, no real leverage. I have a hard time believing that the OEM 3 mounting points flex enough to cause my bolt to be a problem. I think of it like a heavy load spring in a leaf pack on a pickup truck. It doesn't really do anything until there is a lot of load applied and then it should just help carry the additional load. If it is going up and down that much why are they not using the proper mounts (other than they are cheap and the occurrence is rare) which again means my bolt shouldn't "hurt" anything. I do appreciate the feedback though...

 

[bosephbarking]

Guys, there is no metal on metal. The bolt is 5" long but the sub-frame is only 5/8" from the diff cover and the sub-frame is about 3" thick, no real leverage. I have a hard time believing that the OEM 3 mounting points flex enough to cause my bolt to be a problem. I think of it like a heavy load spring in a leaf pack on a pickup truck. It doesn't really do anything until there is a lot of load applied and then it should just help carry the additional load. If it is going up and down that much why are they not using the proper mounts (other than they are cheap and the occurrence is rare) which again means my bolt shouldn't "hurt" anything. I do appreciate the feedback though...

Ford engineering has given you the feedback in the recall. You are free to use that information as you choose. If the diff didn't move that much then the OE bolts wouldn't be bending and breaking.

They aren't using the proper mounts because they either cheaped out or they ran out of stock. You do know that every single Aviator is built with the 2 bolt rear subframe. It wasn't subject to the recall (because it was properly designed).

 

[JCR ST]

BTW what are you guys that are “souping up” your power output doing with the bolt issue?

 

[TMac]

Guys, there is no metal on metal. The bolt is 5" long but the sub-frame is only 5/8" from the diff cover and the sub-frame is about 3" thick, no real leverage. I have a hard time believing that the OEM 3 mounting points flex enough to cause my bolt to be a problem. I think of it like a heavy load spring in a leaf pack on a pickup truck. It doesn't really do anything until there is a lot of load applied and then it should just help carry the additional load. If it is going up and down that much why are they not using the proper mounts (other than they are cheap and the occurrence is rare) which again means my bolt shouldn't "hurt" anything. I do appreciate the feedback though...

You make a good point, but you're missing something. The differential doesn't move up and down in an exact plane, it rotates under torque. As such, the bolt will hit the furthest part of the subframe (your numbers- 3.625" away) well before it will hit the subframe 0.625" away. That's where the leverage comes in.

 

[JCR ST]

The problem is the engineers designed in the two bolts for a reason but the bean counters took 1 out.

 

[JCR ST]

You make a good point, but you're missing something. The differential doesn't move up and down in an exact plane, it rotates under torque. As such, the bolt will hit the furthest part of the subframe (your numbers- 3.625" away) well before it will hit the subframe 0.625" away. That's where the leverage comes in.

That does make sense

 

[UNBROKEN]

That does make sense

If you picture it as it actually functions…it makes perfect sense. If you’re not sure how it actually functions…you probably shouldn’t just start slapping in extra bolts.

 

[JCR ST]

Hearing all your concerns… I took the bolt out to see if there were any witnesses marks from movement. Sure enough the bolt had made contact with the sub-frame on the side closest the the diff. So in an abundance of caution I will leave it out and try to forget about it. Thanks again for setting me straight and without calling me an idiot at least in writing

 

[bosephbarking]

Hearing all your concerns… I took the bolt out to see if there were any witnesses marks from movement. Sure enough the bolt had made contact with the sub-frame on the side closest the the diff. So in an abundance of caution I will leave it out and try to forget about it. Thanks again for setting me straight and without calling me an idiot at least in writing

The product that Unbroken tested on his vehicle is the only aftermarket diff mount I'd use. It ain't cheap but it's designed properly.

The link he provided is:

https://idspeedshop.com/id-speed-2020-explorer-st-rear-diff-brace/

 

[JCR ST]

If you picture it as it actually functions…it makes perfect sense. If you’re not sure how it actually functions…you probably shouldn’t just start slapping in extra bolts.

My assumption was a slight amount of rotational movement, not to the extent that apparently it does. I will try not to “slap in” any more bolts.

 

[JCR ST]

The product that Unbroken tested on his vehicle is the only aftermarket diff mount I'd use. It ain't cheap but it's designed properly.

The link he provided is:

https://idspeedshop.com/id-speed-2020-explorer-st-rear-diff-brace/

Agreed but way too expensive.

 

[R2D2]

Added all weather cargo liner. Ready for the beach side fun.
(My kids second level cleaning, after a beach outing, usually happens here)

KISS Build - Thread covers all the small additions so far.

 

[junlin]

My brakes were warped and just installed OEM rotors and pads last weekend. So much better.

 

[Flyman]

My brakes were warped and just installed OEM rotors and pads last weekend. So much better.

What were you running before you went back to stock?

 

[JRV1631]

Ordered one of these slick-as-snot-should-have-been-OEM little jewels:
View attachment 16879

Always get good ideas from this thread. Just ordered the iOS version.

 

[Toadster]

My brakes were warped and just installed OEM rotors and pads last weekend. So much better.

dang how many miles?

 

[Toadster]

Installed these last evening, really nice quality... love the distressed look

BOGAR TECH DESIGNS - Precut Distressed American Flag Rear Side Quarter Window Decals Compatible with Ford Explorer 2020-2022, Matte Black