alignment after front strut replacement in 2003 525i wagon? Dealer says req’d, mechanic says otherwise.
Required?
As in…a dangerous condition that needs to be fixed?
Or…is the dealership claiming that this is a scheduled maintenance item?
I would tend to trust the word of the indy mechanic, but you might want to get the opinion of one more mechanic, as failure to replace worn struts will have a negative effect on handling, and that is a safety-related issue. Also, your tires will wear more rapidly and unevenly if your struts are worn-out.
If the strut is direct replacement or OEM replacement, there is no alignment adjustment available in the strut’s attachment points. Its dimensions are exactly the same as the strut removed. Unbolt the old, bolt in the new, nothing changes. They are designed to be installed at the factory without need for any alignment except the toe adjustment provided by the tie rod ends.
So, theoretically, you don’t need an alignment. In practice, it is a good idea to check it to make sure nothing is bent or sagged or shifted with age.
Unless your car pulls to one side, wears tires out rapidly, you can put off the alignment, it is not so much a safety item as a maintenance item.
It is recommended and with good reason that an alignment be performed after strut or other suspension/steering work.
Even with struts that have fixed mounting points with no adjustability, the fact is that the mounting holes allow enough movement to throw the alignment off considerably.
A few thousandths or hundredths of an inch doesn’t sound like much in regards to bolt hole slop but it becomes magnified on the wheel circumference.
It’s an unqualified YES. Even if the BMW doesn’t have a camber adjustment, minor differences in camber will result from manufacturing tolerances. The camber will still be within the tolerance for the factory spec, unless the replacement strut is defective. If you look at the geometry of a front end, you will see that any change in camber is will result in a change in toe about 2x the change in camber.
Concur, at least have the alignment checked. Try to make a deal with the alignment shop that if no adjustment is required, you get a discount. It may well be no adjustments will be required, but finding a problem now and fixing it will save you the equivalent amount of money or more on tires later.
In my haste, I thought that the OP was questioning the need for both the struts and the alignment. Upon giving it a second reading, I now realize that he was only questioning the need for an alignment, following strut installation.
All of that being said, I agree that the alignment should–at the very least–be checked.
Alignment after a strut replacement is necessary. OK4450 explained it perfectly. It doesn’t take much to affect handling and tire wear, and no two struts are exactly alike.
Get a printout after the work of the before and after alignment readings (any shop can give you this free… many do as a matter of course) and you’ll see the difference.