Joined the Sag & Tilt Club (and Partially Solved)

[swamp2]

When wheeling in the desert 2 weekends ago my buddy mentioned I appeared titled to one side on flat ground. I kind of just dismissed it and didn't even inspect. Me, no way, I thought.

What I did notice later is that my rear end (just looking at fender to wheel gaps) was quite a bit lower than the front. Prior when closer to stock weight, I put in a small front spring collar to level. Then as I added gear (rack, tent, drawer system, fridge, sliders, CO2 tank, EOS Water System - probably around 600+ lb) I also added a rear spring collar which again leveled the truck and looked close enough to factory ride height. Fast forward to noticing the rear sag, it was significant, over 1".

I got the Hyperco 2" lift HD springs ordered and installed (rears only).

Unfortunately, right when beginning the install I noticed the my right rear was about 1" lower than left rear. Doubly whammy! She was really doing the Carolina Squat on that side.

The new springs (as well as removing the rear spring collars) did just perfect getting the rear sag removed. Vehicle sits very flat with just a bit more arch gap rear than front. Front still has stock springs with collars (dont recall the collar size, it's in my build thread).

Interestingly, the side listing was cur down significantly down to about 1/2". Factory rear springs when removed didn't show any obvious length differences (but hard to measure accurately, so I didn't).

Earlier today I posted this official ride height measurement proceedure and spec from Ford. It says that a 5/16" difference side to side is within specification, so I may be just a bit out. Still need to wheel it good at least once to bother measuring carefully.

Regardless, I kind of got 3 birds with one stone. Removed spring collars (kind of a temporary/hack fix), leveled the rear (vs. front) and now have springs more appropriate for my load and largely corrected the listing.

Big question. Why did my springs take on such a permanent set and why did the left and right do so with so much assymetry? I doubt I am over permitted gross vehicle weight.

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[Bronc5]

The ghost of the ole early Bronco lean from the early daze

 

[monsterfd]

i went through a similar journey and also ended up with hyperco hds front and rear. in my case i hit the LCA mount a bit and I believe it prevented some (or made it difficult to) droop. i dropped the LCA in question and banged out the mount, I also sprayed ptfe in the joint and I havnt had the problem since.

I now have lca mount sliders to protect it.

 

[swamp2]

The ghost of the ole early Bronco lean from the early daze

Do briefly recap for newbies such as me. I know, I know, I could search...

 

[swamp2]

i ... ended up with hyperco hds front and rear.

I like the rears so much, and can pull the front collars off with the HD fronts, so I'll likely get the fronts.

I think my ride was also quite compromised. The rear shocks thought they were always much closer to bottoming, so they very likely ramped up compression damping (continuously) leading to a generally harsh feeling in the rear on mild/medium street bumps/hits. That's now gone.

 

[Bronc5]

Do briefly recap for newbies such as me. I know, I know, I could search...

oh I’m not all into telling people to search stuff or treating strangers bad on the Internet. The first generation of Broncos were susceptible to a condition known as the “Bronco lean“ they didn’t all have it, but it was common enough that it’s still often discussed in early Bronco forums. I actually smiled when I saw this thread as the tradition of Bronco’s carries on beyond just having the cool look. Like the lean is in the Bronco DNA

 

[swamp2]

OK, not entirely solved...

I'm only measuring fender gaps instead of the official procedure which I posted here in its own thread. Given the stiffness of the fenders, it should be a reasonable proxy. Unfortunately, it seems my truck still has a consistent passenger side lean of about 1/2"

Various measurements. Along hub centerline from top outermost knob edge, vertically to fender.

Brand new Raptors (plural) on the lot. Not perfectly flat black top. Fuel unknown.

Front: 7"-8"
Rear: 7 1/2" - 8 3/4"

(consistent with the perspective that stock vehicles need a small front lift to visually look level)

Mine, Rear Hyperco HD 2" lift springs, over 500 lb added load, FMI front leveling collars (not sure exactly thickness), fuel 1/3 full:

FD: 8 1/4"
FP: 7 3/4"
RD: 9 1/4"
RP: 8 1/2"

The official ride height procedure indicates a 5/16" difference is within spec, so I guess I'm out obout 3/16", very small. Official procedure states fuel at or above 1/2 tank. Obviously if I had required fuel levels it would have increased my right/passenger leaning tilt.

 

[TruckCamper]

Park on corner scales and figure out what your corner weights are. May need to shift load. Fuel adds 150lbs or so which will change things.

May be your front passenger spring getting weak as well. As front passenger drops driver rear will raise.
Easy to verify lift one corner and see how it changes the rear load. I've messed with it lot dialing in our 2dr on Icons. Adjusted them for a week daily. Driving between adjustments.

 

[swamp2]

Park on corner scales and figure out what your corner weights are. May need to shift load. Fuel adds 150lbs or so which will change things.

May be your front passenger spring getting weak as well. As front passenger drops driver rear will raise.
Easy to verify lift one corner and see how it changes the rear load. I've messed with it lot dialing in our 2dr on Icons. Adjusted them for a week daily. Driving between adjustments.

Thx. Corners for L-R only? I don't expect F-R will be close to 50-50 (stock or loaded up). You're dialing in pre-load, correct? Adjusting based on corner loads, ride heights or both?

My load is pretty symmetric L-R, but obviously (due to permanently set rear springs) much more rear than front.

Likely need front Hyperco HDs since I have FMI collars and would prefer to get rid of those.

 

[TruckCamper]

Thx. Corners for L-R only? I don't expect F-R will be close to 50-50 (stock or loaded up). You're dialing in pre-load, correct? Adjusting based on corner loads, ride heights or both?

My load is pretty symmetric L-R, but obviously (due to permanently set rear springs) much more rear than front.

Likely need front Hyperco HDs since I have FMI collars and would prefer to get rid of those.

It's a good plan to start with the Hyperco front springs as the stock springs are likely the issue.

Also... only the rear have an HD option. Hyperco only makes one front spring version. However the spring does have higher capacity than stock. It has held our front winch for the past 2yrs and not sagged out.

 

[Hemisfear]

My vote is for the collars...janky lift issues!

 

[swamp2]

It's a good plan to start with the Hyperco front springs as the stock springs are likely the issue.

Thx. I remain curious about the other questions .

 

[TruckCamper]

Thx. Corners for L-R only? I don't expect F-R will be close to 50-50 (stock or loaded up). You're dialing in pre-load, correct? Adjusting based on corner loads, ride heights or both?

My load is pretty symmetric L-R, but obviously (due to permanently set rear springs) much more rear than front.

Likely need front Hyperco HDs since I have FMI collars and would prefer to get rid of those.

Correct. For instance load added/removed from rear driver will affect front passenger and similar for each corner. Corner weight scales are used for race cars to dial in suspension and balance (as one corner is raised/lowered it will transfer physical weight side/side and or front/rear).

We have corner scales and they are rather handy for side to side balance (great for our trailer build modification projects). Front to rear load balance is also a consideration. Things like removing the spare tire has a massive affect on suspension as it sits so far behind the rear axle. Lots can be changed with how you build or load a rig.

Pre load or springs can adjust each corner. Obviously, this is more difficult on the factory coilovers as there is no easy method to adjust. That's why it's best to put good springs on and see how it sits. At least it's good place to start.

Icon coilovers are super easy to adjust. However, really takes a bunch of small adjustments to get heights level side to side and stance front to rear. Once again every adjustment has a corresponding change to the front or rear. Measure (all 4 corners), adjust (one corner), drive, measure (all 4 corners), repeat - key is to only make one corner adjustment at a time as it will change at least one other measurment.

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