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I've been thinking about installing a set of 1.5" leveling blocks (a leveling kit) on the front-end of my 2015 F350 PS (mono-beam axle with coil springs), but I'm getting mixed opinions from others about whether I'll need an immediate alignment afterwards, and why?
So, I've got two (2) basic questions for the experts out there . . .
1) The 1.5" lift blocks insert directly under the coil springs, effectively raising them and the front part of the chassis from the frame, but as I envision it, that doesn't change the positioning of the axle or any critical front-end components (other than the sway bar) in such a way that it should affect the alignment. Have I missed something somewhere? In other words, why should a new alignment (adjustment of castor and/or camber) be necessary if the only real change is a slight raising of the chassis?
2) If in-fact a new alignment is necessary, but I didn't get around to doing one for (say) 6-8 weeks, would it have any adverse effect on things other than some slight premature inner or outer tire wear?
Many thanks for your time and for any responses or opinions provided.
In theory, it will affect your caster by rotating the axle forward slightly (imagine the axle swinging on the radius arms). In actuality, it won't affect tire wear, and probably won't make any difference in steering feel. I would drive it for a bit first and see how it feels before getting an alignment.
Like Tom said..... I've read/heard that doing a front lift/level will reduce castor. Depending on how much lift, and whether or not you drop the radius arms to keep their relationship with the axle right.... thus castor right.
My understanding is that this reduction in castor can contribute to the likelihood of getting the death wobble.
I would get it checked after the lift. Death wobble is something you don't want!
I've had a under spring 2" leveling kit in my truck for 6 years and 60,000 miles. I've never had any steering or alignment issues and never once had the death wobble. I do have a f350 with a snow plow package so it sits pretty high to begin with. I also added a 5.5" rear block the keep the factory rake while raising the truck a little
Like Tom said..... I've read/heard that doing a front lift/level will reduce castor. Depending on how much lift, and whether or not you drop the radius arms to keep their relationship with the axle right.... thus castor right.
My understanding is that this reduction in castor can contribute to the likelihood of getting the death wobble.
I would get it checked after the lift. Death wobble is something you don't want!
Correct. You shouldn't need drop brackets for a small height. A set of castor bushings will fix you up. When reduce caster you'll get the shopping cart feel in the steering and can create death wobble. Swaybar won't be an issue either. You need the alignment to set the castor and that's about it, won't hurt to check everything. It will also not center the steering wheel, just adjust the drag link until its straight.
It sounds like there might be some minor difference of opinion on this topic, and that's not a surprise to me, given what I've heard and read elsewhere. People seem to differ on it based largely upon the extent of the lift involved. For example, most guys seem to agree that anything under 2" of lift is pretty harmless, and shouldn't require too much after-installation adjustments, but I'd sure like to know with some degree of certainly, before I actually perform such an installation.
I'll add that this particular F350 is brand new (less than 2500 total miles), and from what I've read, it sounds like the so-called "death wobble" is most often associated with 'older' vehicles that have already sustained significant wear on the front-end parts. However, despite being a relatively modest amount of lift (1.5"), and despite it being brand new, its sounding like it might be best for me to plan on getting a professional alignment to be safe.
I've had a under spring 2" leveling kit in my truck for 6 years and 60,000 miles. I've never had any steering or alignment issues and never once had the death wobble. I do have a f350 with a snow plow package so it sits pretty high to begin with. I also added a 5.5" rear block the keep the factory rake while raising the truck a little
This is a very interesting and timely summary, and it has provided me with some really great insights regarding my own F350.
When I first took possession of my F350 back in October 2015, it sat exactly like yours, with 3.5" higher (rake) in the back than the front, and it has the so-called "Snow Plow Prep" package. However, I don't currently tow anything super heavy, and I don't have an attached plow, so I chose to drop the stock 4" rear blocks in favor of 2" (F250) blocks, and the truck now sits precisely 1.5" lower in front. This is why I'm now considering a 1.5" lift in front, to help "level" the truck.
Also, I'll add that I've owned a variety of F250s and F350s over the years, some of which were quite high, dating back to about 1982, and I've never really noticed any track-ability or steering instability with any of them. However, this new 2015 F350 does in-fact seem to demonstrate some minor yet somewhat troubling instability, particularly at higher speeds, and particularly on turns. It could be an anomaly or even my imagination, but in a word, this truck feels a bit more "top-heavy" than earlier F250/F350 models that I've owned, and you can really feel it on medium- to high-speed downhill turns.
And lastly, it occurs to me that the sheer weight of your entire snow plow assembly may help discourage "death wobble" or any sort of front-end instability on your particular truck.
I have a 2.5 lift on a truck with 30k miles it was aligned after the toe was out but it could of been wear, caster was just in as I didn't get caster shims, . My understanding is death wobble occurs only on coil sprung front ends that are wore out somewhere. Otherwise I would say I should have it.
In my opinion, and it's just that, an opinion. I have no data to back this up. If the lowest 250 and the highest 350(roughly 3" difference) use the same suspension and steering parts, it would seem to me that there is a lot a flexability built into these parts and that a 2-3" lift probably wouldn't effect it a lot.
You can't skip the alignment shop. Granted you won't change the toe but you need to know what the castor is. In my opinion you want to keep is on the more positive end of the range. You'll also be surprised how far the toe is out from the factory, mine was horrible.
As the OP (or original poster) of this thread, I'd like to briefly revisit this discussion, because I'm continuing to get mixed information from so-called "alignment professionals" in my home town, so I'm going to go ahead and re-open it here:
I'm now hours away from finally installing a set of leveling blocks under the front coil springs of this 2015 F350, and instead of using 1.5" blocks (cited above), I'll be using a slightly taller set of 2.0" blocks, but tech support reps for the manufacturer of these blocks have indicated two (2) specific things that they say need to be re-adjusted in the subsequent alignment process:
1. Caster or Castor (they say it should be adjusted slightly more "negative")
2. Tow-in (they say it should be adjusted ever so slightly inward by < than 1-degree)
I spent a fair bit of time on the phone with these tech support reps and they sure seemed to know what they're talking about, but then I stopped and spoke with an alignment tech at a local Meineke Tire store (which is considered to be the best alignment shop here in my area), and to my dismay, they said that the re-alignment would not involve any adjustment of the castor/caster or the tow-in at all?
Can someone help clarify this or help educate me on just what "castor" (or caster) is, and which one of these two parties is likely to be correct on this issue? Why are they each telling me two different things? Will the castor (or caster) need adjustment? And what about the tow-in?
1. Caster or Castor (they say it should be adjusted slightly more "negative")
2. Tow-in (they say it should be adjusted ever so slightly inward by < than 1-degree)
Correct on both accounts. Although the toe in is not as important and the caster.
Originally Posted by Puckhog
I stopped and spoke with an alignment tech at a local Meineke Tire store (which is considered to be the best alignment shop here in my area), and to my dismay, they said that the re-alignment would not involve any adjustment of the castor/caster or the tow-in at all?
Why are they each telling me two different things? Will the castor (or caster) need adjustment? And what about the tow-in?
The guys at Meineke may or may not be right. They can't know until they get the truck on the rack and actually take readings of the caster, camber and toe. Until then, it's all just speculation.
The 2" blocks my or may not throw you out of tolerance. Depends on what your starting point is as the truck sits now. There is a little bit of leeway in the adjustments as to what is "in spec".
Do your lift, take it to the shop, have them put it on the machine, and ask to see the readings. They should be able to show you live read outs while it's on the machine. If not, demand a print out. Ask them to get the truck to the more negative end of "in spec" caster settings.
Negative caster is the biggest player in preventing the death wobble. Right next to not having any worn out parts or out of round and/or unbalanced tires/wheels.
I'll be watching this thread because I plan to do a lift/level on my truck this year and want to avoid any problems too.
When u look at the front wheels from the side and u draw cross hairs over the tire this is where it starts , now roll the front wheel on a pivot from the back torsion bar like u would on putting a lift on the cross hairs now lean to the front that's the caster of ur front wheel . They make caster shims for this but there's 3 degrees of negative caster built into a new truck u lose 1 degree per inch of lift so 2 inches u will still have negative 1 degree . You are still good . People talk about death wobble negative caster hides it some . It don't fix the problem , death wobble is caused from worn parts any single part could cause it. The more worn part the more severe.
I went looking for articles to link you to to help explain it, and now I'm confused as to the proper terminology.
One site says you need positive caster - I know it s a Jeep site, but they have similar axle designs - HERE. Scroll down to section 2.
"2. SET YOUR CASTER:
You ever get a shopping cart at the grocery store with a bum wheel? You know, the kind that wobbles all over the place even though you're going straight. This occurs because for whatever reason, the wheel in question has very little to no positive caster on it. Likewise, a Jeep with little to no possitive caster can instigate death wobble as well. Lifting a Jeep will effect your caster and it is important that you have it set as close to the factory +4.2° as possible. Having more is better but, that can cause driveline vibrations and that's not something you'd want to have."
But then this site, also a Jeep site, calls it negative caster - HERE
Scroll down to section 6.
"6. Check the caster angle. A lift kit tends to change the caster angle toward zero degrees, and sometimes even a positive angle position. Casters must be at a negative angle to operate properly. A minus 4 or 6 degree angle is generally required. Research the caster spec for your vehicle."
So now I'm confused too.
Regardless of what it's called, I believe , when looking at the vehicle from the side, you want the top ball joint behind the bottom ball joint. Like this showing positive:
Or do I have it backwards for our trucks? I'm so confused now!
A leveling kit or any alterations if suspension height will not change the toe. That is held in place by the steering link that spans the knuckles. Granted it could be out of spec but the leveling kit won't cause that. Altering suspension height will create issues with track bar and drag link length and bump steer. With such small height in a leveling kit there's not much issue here. Most you will need done is to adjust the drag link to recenter the steering wheel. Castor is by far the biggest player, it not only is a big factor in death wobble but also is what pulls the wheels back to center. Castor is the angle of the upper and lower ball joints in relation to vertical. You want the upper to be behind the lower, think of the rank on motorcycle forks. As you lift you truck the axle pivots down at the end of the radius arm making that ball joint angle more vertical or go the other way. With a leveling kit the change is usually minor enough that you can fix the castor angle with a set if offset bushings at the upper joint. I believe 2 degrees is about the max for a bushing. When to get past what a bushing can fix you need to lower the radius arm pivot, and more extreme/custom cases cut the knuckle off an rotate it to the correct angle and reweld it. An alignment and a set of bushing is all you should need. Bad part is you need to align it after the leveling kit and possibly have to order bushings, install and align again to verify correct castor. To be honest most chain stores don't have a clue. Where ever you are looking to go they should be able to pretty much verify what you heard already, if not move on to somewhere else.
02-05-2016, 04:02 PM
