Dual Mount Rear Diff Plate/Bushings install help

[jwagman1]

I got the subframe dropped on maintenance bolts and started removing the 2 bottom rear diff plate bolts ( 2 on bottom, 1 on top). The bolts are extremely hard to turn. my bro and I spent an hour and got 1 out but the 2nd bottom bolt is way harder. I tried standard wrenches and a breaker bar and it barely budget a 1/8 of a turn at a time. Tried soen wd40 but was no help. Should I torch the diff to loosen them? ...If thr top one is just as tight I have no idea how I am going to get it out since there's no way to get the breaker bar on top without completely dropping the subframe to the gound. Any advice? anyone else have issues with these bolts??

BTW 42k miles and my oem rear bushing was destroyed. 2015 f80 636ft-lb

[b_w.]

Be patient, they have locktite on them. I do the top one from the side with a breaker bar and longer socket

[jwagman1]

Originally Posted by b_w.

Be patient, they have locktite on them. I do the top one from the side with a breaker bar and longer socket

Yea the 2 remaining won't budge with the breaker bar. I feel like the bolt head is going to shear off... gonna try a torch just never done that before.

[jwagman1]

Update:

The bolts are out! It took penetrating oil and heating the bolts with a torch until they are red hot, even then the top bolt was a f'ing bitcch! Took 2 of us with a prybar pulling on it together for 60m to get it out. Red locktite is no joke! My forearm muscles are destroyed! We were able to get to the top bolt with the breaker bar by going in from the driver rear wheel we'll then finding spots underneath the put our arms up around the suspension to grab and pull.

For anyone attempting this install, you gotta be super patient and have help. By far the roughest install I've done on the F80. F those bolts!

[jfritz27]

Glad you got it done! Sounds like maybe you were particularly unlucky with those bolts, I don't recall anyone else reporting that much trouble.

I plan to do this at some point over winter, with a buddy. Will be sure to soak everything in penetrant starting the night before

[Ryan5034]

For others doing this task and another data point I had the same troubles. All 3 bolts were mega hard to remove. I’m replacing them as well fearing for their strength.

[Track/S]

Originally Posted by jwagman1

Update:

The bolts are out! It took penetrating oil and heating the bolts with a torch until they are red hot, even then the top bolt was a f'ing bitcch! Took 2 of us with a prybar pulling on it together for 60m to get it out. Red locktite is no joke! My forearm muscles are destroyed! We were able to get to the top bolt with the breaker bar by going in from the driver rear wheel we'll then finding spots underneath the put our arms up around the suspension to grab and pull.

For anyone attempting this install, you gotta be super patient and have help. By far the roughest install I've done on the F80. F those bolts!

First you have to remove the diff, and with it on the ground, you can easily remove it with an impact wrench.

[Rokoz]

That top bolt was the difficult one for me - I'd definitely echo using some heat on them