Alignment needed?

[LisaLannister]

I ordered a pair of Suplex rear coil springs and I am going to have a local mechanic install them and they also said I would need an alignment.

Is an alignment necessary when replacing rear springs?

Thanks

[jhm5]

If it changes the ride height, yes, as that will have an impact on other angles. I'm guessing that you are replacing broken springs?

[LisaLannister]

Hi jhm5. I am replacing the two rear cracked springs (they both separated at the bottom). .

[jhm5]

That's a common problem on E46/E85/6 BMWs, especially where road salt is common. Make sure shop is familiar with BMW specs and front and rear alignment.

[T-Bears]

Anything that changes the geometry of the suspension will require an alignment. A new spring with a different rate & ride height will most likely alter your camber which will then require an alignment.

I usually take my car to BMW for alignments they know the specification for our models and it saves time and money.

[belcom]

Originally Posted by T-Bears

I usually take my car to BMW for alignments they know the specification for our models and it saves time and money.

They sure do but so does every alignment machine/computer in any shop that does it. Pretty sure there's a universal database with all the factory alignment specs for every car out there.

Although, there are also shops that do it manually with some old school equipment. Not sure where these guys get the numbers but it can't be that hard to find I suppose. I know of at least one shop like that and they're very highly regarded and known in and around Toronto. They do an awesome job no matter what car you have.

OP, since you're replacing just rear springs I would imagine what you've bought are OE replacements which means your rear end should end up at about the same height as originals. In that case you probably don't need an alignment however it really doesn't hurt to do a proper 4 wheel alignment every 2-3 years if the car is driven regularly.

By the way, replacing the rear springs is quite easy. Just get a buddy, a couple of beers and exercise safety at all times

[T-Bears]

Originally Posted by belcom

They sure do but so does every alignment machine/computer in any shop that does it. Pretty sure there's a universal database with all the factory alignment specs for every car out there.

Although, there are also shops that do it manually with some old school equipment. Not sure where these guys get the numbers but it can't be that hard to find I suppose. I know of at least one shop like that and they're very highly regarded and known in and around Toronto. They do an awesome job no matter what car you have.

I'm sure most places can align to BMW specs if they wanted to it's not difficult. However, the last few places I have been to have either made my steering wheel crooked, have the steering wheel pull to the left, or not a perfect alignment.

It's all about knowing a good place, and at the time I needed an alignment there was only Firestone and LesScwab near my area and both couldn't get it dialed in on my Z4. I only go for perfect alignments and not acceptable value ranges.

At the time Roger Krause Racing was my go to guy for alignment but he was 1.5 hours away, so I went to Santa Rosa BMW dealership nearby and poof problem solved. I'm now in the Los Angeles area and know a few decent alignment shops within 20 minutes away yay.

[rsutoratosu]

My friend works at BMW, I specifically ask him about lowering cars and he said they would be guessing because the computer can't handle lower heights.. they only have factory specs. Unless each dealer uses a different type of machine. He say my best bet is one of those hunter alignment places that works with lower cars. Originally I wanted him to do my car because he wont fk up my car

[belcom]

Originally Posted by T-Bears

I'm sure most places can align to BMW specs if they wanted to it's not difficult. However, the last few places I have been to have either made my steering wheel crooked, have the steering wheel pull to the left, or not a perfect alignment.

It's all about knowing a good place, and at the time I needed an alignment there was only Firestone and LesScwab near my area and both couldn't get it dialed in on my Z4. I only go for perfect alignments and not acceptable value ranges.

Yikes. Human factor will always be present Whoever left your car with a crooked alignment probably have their hands growing out of their arse.

I totally agree with you on the fact that you should only use trusted shops and people to take care of your Z.

I just recently did alignment and corner balance by a guy who literally has a shop on his property where he lives but he's also a professional racing instructor and an car/marine/industrial mechanic with tons of experience. No fancy shop fronts, but he really knows what he's doing. Was recommended to me by another shop who could not get my car on their alignment rack because it was too low (but its not really that low).

When I left the car was driving like its on rails and straight as an arrow. And on top of that he only charged half of what other BMW indy's quoted me and was done in an hour. Awesome guy and I will recommend him to anybody with confidence.

[T-Bears]

^Very Nice, I haven't done a corner balance since I sold my track Miata. A good suspension setup & alignment really changes the way a car moves. Iv'e always had a hard time finding an honest shop. I used to go to a nice shop that I once worked for while in school that specializes in German cars but my old boss retired.

Not to thread jack, but the heatwave we had all week caused my transmission to slip, now I'm looking for a decent shop that I can take my car to for a transmission flush. Hopefully, that will improve the situation because I'm on my second transmission. The previous owner had the tranny replaced at 100k with a used one.

[T-Bears]

Originally Posted by rsutoratosu

My friend works at BMW, I specifically ask him about lowering cars and he said they would be guessing because the computer can't handle lower heights.. they only have factory specs. Unless each dealer uses a different type of machine. He say my best bet is one of those hunter alignment places that works with lower cars. Originally I wanted him to do my car because he wont fk up my car

Hunter Alignment racks seems to be the popular type of machine down here in Southern California. Is your Z stock ride height? I have the Sport Suspension and I'm always trying to be careful to avoid scrapes.