[Surly73]

It's time for me to get an alignment again. For the first time I'm thinking of diverging from "factory" and giving the shop custom targets for the rear. My intent is to dial out some of the factory negative camber and negative toe to improve rear tire life.

A couple of years ago I remember reading BMW-specific threads about this, but I cannot find them now. I read first hand accounts from folks who went for "barely negative" on each, and someone else who approached with a "cut it in half" idea. I believe both said that in normal-to-spirited North American driving they didn't notice any downsides and improved rear tire life quite noticeably.

Any experience here with this idea?

For what it's worth my KW's have me dropped about 1" from factory (still have one finger gap) and I now have about -1* camber on the front due to the drop. All other factory targets can be met. I run factory option 351M 19s 245/40/19 square setup in the summer so nothing extreme.

[Unspec]

Oh, hello from Reddit

The shop I go to, AZP installs, typically does factory camber and then tries to get toe close to zero. I didn't actually get to zero toe on the front cause the tie rods were seized and they were stuck at the factory spec (luckily). I plan on changing them out soon and going back for an alignment to get zero toe.

[Surly73]

That sub is so hit or miss. If I see one more post asking about an engine noise shot with a phone from inside the cabin blipping the throttle with the windows up I might lose it. Step 1: open the big, body colour hatch at the front of the car...


I was thinking of toe target just slightly negative. Zero toe in the rear would be a significant change. How close did the shop get for you and.... how is it to drive compared to factory alignment?

(I've been dousing my tie rod end threaded sections with penetrating oil every couple of days for the last 1.5 weeks leading up to this job)

[Blue Angel]

I've gone for minimum toe-in on most of my previous cars, and by minimum I mean as close to zero as possible without going positive. This is good for reducing tire wear and improving turn-in response, but can lead to a car that wanders at speed and is affected by cross winds. I'm OK with that and once you're used to it it's not bad, but if someone else drives your car it might be unsettling.

With my F10 I went for the minimum toe spec that still had it in range. I find it's still very stable at speed, and I sleep well knowing I'm not causing excessive tire wear.

In the front I'm lowered with -0.5 degree camber arms, so it sits at -1.3 degrees. I had them match the rear to the front (-1.3 degrees all around), which reduced rear negative camber by about 0.5 degrees.

I'm lowered on coilovers (12k front and 8k rear springs) with stock 535d sway bars, and the car is extremely neutral. I've played with it extensively on wet off ramps and in the snow this past winter, and if anything it might be slightly tail-happy. X-Drive and stability keeps things under control. I would like to try a very mild upgrade in front sway bar stiffness to see if it takes some of the play out of the back, but to be honest it doesn't need much and I'd be concerned with overdoing it and ending up with understeer.

On the topic of camber... why BMW puts so much rear camber into their cars is beyond me. I'm 100% sure there's a solid Engineering reason for it, but that reason escapes me and may be poorly justified. -1.8 degrees of camber on a car that uses up to 275 width tires with low-profile super stiff run-flat sidewalls is simply a recipe for tire and wheel destruction.

[Unspec]

Originally Posted by Blue Angel

On the topic of camber... why BMW puts so much rear camber into their cars is beyond me. I'm 100% sure there's a solid Engineering reason for it, but that reason escapes me and may be poorly justified. -1.8 degrees of camber on a car that uses up to 275 width tires with low-profile super stiff run-flat sidewalls is simply a recipe for tire and wheel destruction.

Sigh, this hits me hard lol. I'm actually close to -2. Running 343M's with even 275's on the rear with KW v3's make me rub on stock camber. Might need to just suck it up and sacrifice the rear wheel gab and raise it up a bit to run closer to stock camber.

Originally Posted by Surly73

That sub is so hit or miss. If I see one more post asking about an engine noise shot with a phone from inside the cabin blipping the throttle with the windows up I might lose it. Step 1: open the big, body colour hatch at the front of the car...


I was thinking of toe target just slightly negative. Zero toe in the rear would be a significant change. How close did the shop get for you and.... how is it to drive compared to factory alignment?

(I've been dousing my tie rod end threaded sections with penetrating oil every couple of days for the last 1.5 weeks leading up to this job)

Lol that sub is mostly vague technical help and "lol look at this upbadge, let's shame them!". Very little quality content.

I actually stuck with factory toe in on the rear, and they recommended it as well. They were aiming for zero toe in on the front but was unable to hit it.

Did the penetrating oil thing work?

[Surly73]

Thanks to all for the additional comments - it gives me some idea.

Originally Posted by Unspec

Did the penetrating oil thing work?

Sadly, I don't know. The shop I was all set up with had their machines go down with hardware problems and chip shortage/supply chain has an unknown repair time. I'm considering getting my replacement rear tires mounted at the dealer and holding off on the alignment.

I'll keep hitting the tie rod ends with penetrating oil now and then until I can get in. I really don't want an otherwise-unnecessary tie rod replacement job added to the bill (or my DIY todo list).

[Surly73]

Originally Posted by Unspec

Did the penetrating oil thing work?

Nope. Hit them more than half a dozen times since April. In for alignment today - both tie rod ends are seized. I also fuss over them as part of my pre-winter and post-winter clean ups and anti-corrosion protection.

I'm going to have to come up with something so that I'm not on a tie rod subscription plan.

[Blue Angel]

Originally Posted by Surly73

I'm going to have to come up with something so that I'm not on a tie rod subscription plan.

LOL! I think that may have been what BMW had in mind!!!

Considering how well Engineered most of this vehicle is, the tie rod design seems intentionally bad. The good old jam-nut style tie rods are significantly better than this, and once you get them properly lubed with anti-seize they're usually trouble-free. They're probably much cheaper to manufacture as well, so yeah… a lose-lose situation.

[Unspec]

Originally Posted by Surly73

Nope. Hit them more than half a dozen times since April. In for alignment today - both tie rod ends are seized. I also fuss over them as part of my pre-winter and post-winter clean ups and anti-corrosion protection.

I'm going to have to come up with something so that I'm not on a tie rod subscription plan.

When replacing the tie rods, slather some anti-seize on the threaded portion that goes into the outer tie rod/ball joint side. Should make it far, far better.

[Surly73]

Originally Posted by Unspec

When replacing the tie rods, slather some anti-seize on the threaded portion that goes into the outer tie rod/ball joint side. Should make it far, far better.

Well, sadly for my wallet this tie rod replacement wasn't DIY. The indy I use for whatever I can't do myself (like alignments) is pretty competent generally and we had a chat about the use of anti-seize but it doesn't seem to matter.

I wonder - is this a part I can take apart as a separate action from adjustment and add more anti-seize or plain old grease? I have just this summer purchased some marine grade anti-seize that I'm going to try in stuff that actually sees the road salt all winter, like hubs etc... I might try some of that on the tie rods.

Or, if they can be disassembled without necessarily affecting the adjustment, maybe I just make sure to loosen/tighten them every spring and fall?

I'll have to do a little research.

And OMG, the car was doing some weird stuff pre-alignment. I knew it was time. I was a little worried I had to track down a bad bushing or ball joint somewhere. It wasn't even terribly out on my before/after but it was SO sweet on the first drive with the fresh alignment. All the issues were sorted out. People say it's strange that I can notice these things. The summer rubber is very unforgiving.

I raised the ride height another 5mm too pre-alignment. I'm not even that low (like 30mm lower than factory on a non-M sport) and it was getting a little much for scraping and hitting things.

I think it actually looks better now and buys me a little more room for road hazards.

[Blue Angel]

Alignment has everything to do with how a car feels/handles, and the relationship between how heavy the car is to how big/sticky the tires are seems to be a thing too.

I have an 02 ZO6, a featherweight by today's standards at 3100 lbs. I have 285/305 R-compound tires on it and have done lots of messing around with alignment over the years.

A proper alignment makes that car feel absolutely nailed down and completely stable, totally confidence inspiring. If one of the eccentric adjusters slips a little (common on the C5/C6 platforms) the car can go from superhero to sketchy in an instant. This is amplified significantly when driving on wet roads.

The culprit is toe. Stiff sidewall low profile tires don't have much give, and excessive toe causes them to scrub and fight each other for traction. It also causes accelerated wear on tires and wheel bearings, wastes fuel, and causes spooky handling characteristics.

Too little toe and the car can lose directional stability and wander around while driving straight. Personally, I prefer this and usually shoot for zero or close to it.

The F10 comes with everything from pillow-soft 17" marshmallow all-seasons to rock-hard 30-series 20's, yet has a single alignment spec for all models. I believe the only exception is the "low slung" model, but these cars are very rare and the alignment specs are almost identical anyway… I believe the only significant difference is front camber, which changes with ride height and isn't adjustable.

[Surly73]

Originally Posted by Blue Angel

Alignment has everything to do with how a car feels/handles.

Completely agree. It just didn't take much for my F10 to have lost it's good-ness. For the last 20 years I can usually tell when it's time, and sometimes the adjustments are small. As you say, top tier rubber really points it out.

I did ask this shop to shoot for less toe (although still toed in slightly). Pre-alignment I was getting very noticeable pulling from road crown (e.g. you go to pass on a two lane road and as you cross the yellow line you get some yanking on the wheel). I was concerned there was something more going on but it's all good now.

On my first alignment after the coilovers at the original ride height I had about -1* front camber I couldn't dial out. With the ride height +5mm now I'm ~-0.5-0.6 which will probably be just nice.

I left them with the TIS sheet for the "low slung" F10 as a data point, which still rides quite a bit higher than mine.

[Blue Angel]

I find the same thing - excessive toe in causes the car to pull and wander around on uneven road surfaces. I have 275's on the front of my F10 and the steering feels great, no pulling or "tramlining" on uneven roads, with toe set to the minimum spec.

That also includes front camber at -1.3*, which I was initially somewhat concerned about. I think this is a testament to the excellent geometry designed into the F10 suspension/steering. I suspect there's very good control over the scrub radius.