Alignment Question - Page 3 - PeachParts Mercedes-Benz Forum

JamesDean · #31 01-30-2013, 03:18 PM

I had my dad call the dealership as I am at work...

Talked to Larry..in service...not too much help
they have no guarantee that comes with the alignment
because of the road conditions and all the adjustments...he
was not sure about the spreader bar..said that they would follow
what ever the Mercedes process calls for.

...hmmmm

Silber Adler · #32 01-30-2013, 04:43 PM

Hi JD
How does your car drive when compared to previous, before the alignment.

Was there a reason that you took it in? Tires wearing funny, pulling?

The best alignment guy around here works with very basic tools. No electronics. Everybody swears by (not at) him. His place is in a flood plain and about every other year he puts his tools up on high shelves and closes down.

JamesDean · #33 01-30-2013, 06:08 PM

Quote:

Originally Posted by Silber Adler

Hi JD
How does your car drive when compared to previous, before the alignment.

Was there a reason that you took it in? Tires wearing funny, pulling?

The best alignment guy around here works with very basic tools. No electronics. Everybody swears by (not at) him. His place is in a flood plain and about every other year he puts his tools up on high shelves and closes down.

See this is what I am never sure of...

Was my car simply out of align?
Are they an incompetent shop when it comes to MB?
Did they do it right and it reveals a worn steering part or something?

Is my steering box getting sloppy?

I'd replaced both front springs as one was broken. This raised the front end of the car up by a good two inches or so. I can't remember 100% right now why I took it in but It seemed like it was pulling. I also had new tires put on just a few days prior as well.

My 190E has all new suspension and a rebuilt steering box. I am hesitant to let them align it...

The dealer has not instilled any confidence in my dad as the guy seemed a bit clueless on the spreader bar question.

Silber Adler · #34 01-30-2013, 06:53 PM

The reason I asked was because I have never noticed much difference in the way the car drives when I have had them "aligned" I am excluding the couple of times that I have bent suspension members from going off the road and such.

Actually to my limited knowledge the original numbers didn't look that bad. Sure some were not to what another mercedes had but still they were both pointed down the road. All of the wheels are suspended in rubber bushings and probably flex at least a degree when running down the road.

Not saying any thing about your experience but confirms my suspension ideals "if it aint broke don't fix it. "

My guess is that once you drop another couple of bills at the dealer it will drive about the same. Hope I am wrong.

JamesDean · #35 01-31-2013, 08:33 AM

Well most of the time when I take a car in for alignment I usually can tell/feel a difference afterwards and looking at the before and after measurements of all my alignments there was clearly something amiss.

You are correct the bushings and such would flex when driving down the road, which is why Mercedes says you should perform certain points of the alignment with a spreader bar..to pre-load the bushings so that you alignment numbers take effect when the car is on the pavement.

In the 190E, there was definite slop in the gearbox. I replaced that and the steering/handing is vastly improved. However the toe needs adjusted as the gear box was installed like one or two splines out of perfectly straight. I am leary of just taking this to the place I've been going. I spent oodles of money on the suspension rebuild. I dont want to get it aligned and not be happy with the results only to have to have it REDONE by someone who can do it right.

I think what I am going to do is:

1) Have the dealership check the steering box/linkage for slop.
2) If its within spec, perform the alignment as per Mercedes spec. Use the spreader bar as called for. According to what I've seen, every Mercedes requires one to preload the suspension.

Everyone uses a spreader bar for alignment?

So far I've only gone to two places for alignments. One I was not happy with any of the results nor do I particularly like going to them (there was an incident involving my 190E and some parts I had just installed, and they blamed me for something and said I installed the wrong MB parts or something) and the other place I had them align the 420SEL. The alignment was satisfactory however the 420 needs a front end rebuild so there is slop everywhere..

On a side note...I read somewhere that Hunter requires people to buy the spreader bar when they buy a new machine...or something to that extent..

raysorenson · #36 01-31-2013, 09:04 AM

Hunter didn't mention the bar when we got our new machine a few months ago, but we're a Ford dealer. As I said, I don't see the spreader being deal breaker. I've aligned my Merc fleet without it and I'm satisfied that the results are as good as they're going to get, considering all the bushing mush that Merc designed into their suspensions. If you get some nice stiff poly LCA bushings, the spreader bar shouldn't be used and your front end will gain more bite in corners than you thought possible. All that caster is pretty nice when your bushings aren't moving all over the place.

FYI, it's not accepted practice to adjust toe to correct spline offset. The spines should be clocked correctly, otherwise gear mesh will be messed up and your pitman/idler arms won't be oriented correctly and your linkage geometry will be thrown off.

JamesDean · #37 01-31-2013, 09:09 AM

Quote:

Originally Posted by raysorenson

Hunter didn't mention the bar when we got our new machine a few months ago, but we're a Ford dealer. As I said, I don't see the spreader being deal breaker. I've aligned my Merc fleet without it and I'm satisfied that the results are as good as they're going to get, considering all the bushing mush that Merc designed into their suspensions. If you get some nice stiff poly LCA bushings, the spreader bar shouldn't be used and your front end will gain more bite in corners than you thought possible. All that caster is pretty nice when your bushings aren't moving all over the place.

FYI, it's not accepted practice to adjust toe to correct spline offset. The spines should be clocked correctly, otherwise gear mesh will be messed up and your pitman/idler arms won't be oriented correctly and your linkage geometry will be thrown off.

Hmmmm. The LCA bushings on the 300D are not particularly old. I think my records show they were replaced in late 2010. The rear end however, has not had any work done as far as I am aware.

I had just assumed it was a spline offset issue. If I did take it to an alignment shop and they discover that the spline offset is incorrect is that something that they would correct? Or would I have to take it back to my original shop then back to the alignment shop?

raysorenson · #38 01-31-2013, 09:39 AM

IMO, brand new bushings are too soft to adequately maintain alignment, hence the spreader bar. New LCA bushings are one of the first things I do to new additions to the fleet. Just coil spring force on the lower control arm is enough to cause visible bushing deflection- even on a brand new bushings. They do a fine job of insulating the chassis from vibration, a poor job of maintaining alignment angles.

Is your wheel 90* off center or just a little off? There's no guarantee that correct spine alignment will put you wheel exactly where it was before, but if your wheel is off center enough to be improved by re-clocking the splines, if even by one spline, then it's best to go that route before aligning. FYI, it's pretty simple DIY. Just take the pinch bolt off by the rag joint, pry the steering shaft into the firewall, twist and slide back in.

JamesDean · #39 01-31-2013, 09:43 AM

Quote:

Originally Posted by raysorenson

IMO, brand new bushings are too soft to adequately maintain alignment, hence the spreader bar. New LCA bushings are one of the first things I do to new additions to the fleet. Just coil spring force on the lower control arm is enough to cause visible bushing deflection- even on a brand new bushings. They do a fine job of insulating the chassis from vibration, a poor job of maintaining alignment angles.

Is your wheel 90* off center or just a little off? There's no guarantee that correct spine alignment will put you wheel exactly where it was before, but if your wheel is off center enough to be improved by re-clocking the splines, if even by one spline, then it's best to go that route before aligning. FYI, it's pretty simple DIY. Just take the pinch bolt off by the rag joint, pry the steering shaft into the firewall, twist and slide back in.

The 190E actually have sport bushings in the LCA's. Hopefully a bit stiffer than the normal/stock level rubber. I imagine the 300D has stock level of firmness bushings in it. It will undoubtedly need the spreader bar. I've read many threads on many MB forums that indicate the need for a spreader bar or equivalent to do the alignement right for the exact reason we're discussing here.

The wheel is maybe 5-10 degree off. Not 90. Its been a while since I've driven the 190 so I may be recalling incorrectly but I do know that it was NOT enormously off.

raysorenson · #40 01-31-2013, 11:18 AM

There's probably around 30 splines on the input shaft, 36 would make 10* per spline.

Junkman · #41 01-31-2013, 11:25 AM

One description that I read by someone who does may MBZ alignments is that he does not use the spreader bar and has gotten good results. He surmised that the reason is that toe specs cover a wide enough range that he gets close enough without the bar. Apparently toe changes to more negative at speed hence the use of the spreader bar to mimic conditions while driving.

My take on most alignment techs is that they are incompetent and only have a rudimentary understanding. They put the car on the machine and do what the machine says. They don't know how to compensate for worn parts and work on whatever comes in and don't have specific knowledge about a given car.

I've read that MBZ has much more caster than other cars ~10* vs 3* on my truck for example. The larger caster makes steering more tuneable but causes one setting to impact the other. FSM says that changing caster causes camber tp change by approx 1/3. Changing camber causes about a 1 to 1 change in caster.

I had 1 tech give me the SD back with both front wheels tilted to the passenger side. I put it on a rack and saw enough adjustment to do it properly. Apparently the issue was 1 setting affected another and the tech was chasing his tail and gave up.

The next guy gave it back with settings that obviously cause a pull to the right. It does. I haven't had time to take it back but will. There is no adjustment available on the rear and my back tires point right.

My next step is to go back with the FSM and show them how to set things. I think adding more caster to the right will make it steer straight. Ass/u/me - ing the machine is reading correctly, I expect/hope to be done. I haven't found any good places to take the car so am working with what is available.

I intend to change bushings in the rear when the weather breaks. Hopefully that will fix the back alignment. Nothing looks bent.

Phil · #42 01-31-2013, 08:50 PM

I have been much happier with the way my car drives since I started doing the toe adjustment my self and setting the tires to run parallel. I am not wearing out tires so fast and the car handles a lot better than when I had it aligned at a shop.

JamesDean · #43 02-01-2013, 09:56 AM

So here is a question, since I've never actually watch/seen someone do an alignment..

Do they do the alignment with the car on a lift with the suspension hanging? Or on a drive on lift? Wheels on, right?

I was talking to a friend of mine who has a Dodge Charger, which has a decent number of Mercedes designed/influence suspension components, and he said the Charger alignment is done with the car on a drive-on lift so that the suspension is loaded down.

Why is (or maybe it is an I am unware) that the case for the 124?

Im going to have the dealership work on it tomorrow. I figure I would give them a shot. I dont have the time or desire to do it my self really..plus its 10F outside today.. 65F this past Tuesday but 10F today. LOL.

Stretch · #44 02-01-2013, 10:03 AM

The suspension geometry is somewhat different with the weight off - there's little point in aligning the wheels of the General Lee when it is flying; {steering / suspension geometry} it is of more use when the rubber hits the dirt again.

JamesDean · #45 02-01-2013, 10:06 AM

Quote:

Originally Posted by Stretch

The suspension geometry is somewhat different with the weight off - there's little point in aligning the wheels of the General Lee when it is flying; {steering / suspension geometry} it is of more use when the rubber hits the dirt again.

You mean the General Lee can't be steered in the air? Poppycock!