Must I literally ONLY use OE on my BMW!?!

I've complained about this a couple times on here in the past couple days, but I keep having fitment and/or leaking issues with half the things I go to replace on my 2003 Z4. 
 

I thought to myself, "$100 is a bit much for a BMW OE coolant line, yes, I will buy the $30 Rein brand that FCPEuro also sells."

Nope. Leaks at one end. 
 

"$285 is a bit much for a radiator from BMW. I will save some money and buy the $160 Behr Hella instead."

Nope. 1/8" too short so the attachments don't line up. 
 

How about instead of $426 for a BMW DISA valve, I get a $100 Dorman? Better than a $25 Amazon special, right?

Nope. Doesn't truly fit in there. 
 

Okay, maybe I was asking for it with the $35 expansion tank instead of the $132 OE one, but still, it's just a piece of plastic, right??

Nope, OE HVAC hose is leaking and I'm not entirely confident on the two major connections that it sits on. 
 

I suppose I could have split the difference a little more with the other brands offered on FCPEuro, but DANG.

I heard that it cost a lot to maintain a BMW, but before I bought the thing (for a steal, granted) I looked up some of the standard fail point components and saw that you could get typical alternator and radiator prices. Has anyone else had success with any level of off-brand?

You will learn the brands that work.  Dorman fits nothing, and if you wedge it in, it won't last the week.

The Behr radiator should have worked, but it's probably for a model built on Tuesdays by Rolf, not Dietrich.

Germans are lunatics when it comes to using similar, incompatible parts on the same models.

In reply to P3PPY :

I think I may have a DISA or two for a 2.5 Z3 that I would be happy to send your way if you need one.

In the past I've had good luck with OE type brands (loemforder, behr, etc) but I have noticed quality slipping in the last few years. Generally these parts are still better than the Asian brands but they're aren't flawless as they used to be. 
 

dorman isn't worth your time. 

In reply to Streetwiseguy :

Unfortunately I got that piece from RockAuto who is particularly inconvenient about returns. I'll often look up parts on RA and find them on Amazon for just such a situation as this. 
 

Woody, I'll have to look up compatibility for those. While trying to mash it in there today I read about differences between the 2.5 and 3.0. Thank you for the offer no matter how it shakes out, I'll get back with you. 

You couldn't have waited to post about this until after my 128i sold? ​​​​​​

It's not just BMW.  A lot of aftermarket parts are made insufficiently well, for all makes.  I think it's because they either overconsolidate applications, or everyone copies off of the first aftermarket part which happened to have been made wrong.  Or both.

The other fun part is that a lot of the time, the original part manufacturer may have two tiers of QC, one for the car manufacturer and one good enough for their internal standards.  Monroe made the struts and shocks for my Volvo, and you can buy Monroe labeled units for about 2/3rd the price of Volvo labeled units, and while it is "the same part" (made in the same factory/same production lines) the Volvo labeled ones last longer/perform better.

In reply to Pete. (l33t FS) :

TIL that Pete gets up very early in the morning. 

In reply to P3PPY :

If you deal with the reputable independent parts suppliers, they can often source parts that are made by the OE suppliers but just aren't in the factory BMW box.  I have had good service from Blunttech, but there are others.

Ive had good luck with the "other" brands that FCP Euro sells. Thats on my 1995 E36 though. 
 

In general, I use OEM for belts and hoses. Too many FLAPS belts and hoses just dont fit. Close maybe, but hoses and belts arent horseshoes or handgrenades. 

FCP Euro is the easy button.  They only sell OE or OEM.  If you have a low-buck project, you can go to FCP and figure out the OEM and then go buy that from Rock Auto.  But I almost never do that because FCP is a great company that I want to support.

FCP Euro would have been my answer to the problem as well.  But it looks like the OP went that route and still found that the FCP-provided option wasn't quite right.

stuart in mn said:

In reply to P3PPY :

If you deal with the reputable independent parts suppliers, they can often source parts that are made by the OE suppliers but just aren't in the factory BMW box.  I have had good service from Blunttech, but there are others.

Steve is the man! 
Also Levent at GutenParts. 

For the most part, I've used OEM parts on various BMWs over the years without issues. That said, however, more and more of the old standbys in the German car world - Lemforder, Febi, etc. - have moved significant production to China. Some of the China stuff has been fine, but I've seen a few pieces that didn't seem up to snuff. Fortunately, FCP is easy to deal with, so at least you don't get stuck with ill-fitting crap without recourse.

Of course, BMW itself doesn't always get it right either (cough, two separate recalls for PCV heaters that burst into flame, cough...).

Kyb makes the oe struts for my Highlander, but the aftermarket kyb units are terrible for the same application. This is in a 20 year old boring DD and I still notice the difference. 

In reply to RaabTheSaab :

Same experience with KYB and my LS400. The aftermarket struts were also about 1" taller than OEM.

Nevertheless I still use "well it's the OEM supplier" logic. Hopefully the Aisin water pump from rockauto is as good as the dealer's.

Good question!  I've had some similar problems with my E30 BMW rally car.  I mostly don't buy OEM, and if RockAuto sells it, I buy it from them.  Some lessons: I no longer buy anything "Uro" branded--it's almost universal garbage.  Since I just learned that FCP will actually take returns when they sell me crap, maybe I'll start buying more from them.  I love RockAuto, but I've never successfully returned anything to them even when their site is just completely wrong, but that rarely happens.  I've had pretty good luck with Mahle, Rein, Meyle, Febi...  

I'm sure it's a problem with other makes too, but this is part of why I'm swearing off German cars.  (I own two Audis, an E30 rally car, and race a Formula Vee.  I'm never buying another German car.  Really.  I can stop any time.)  In the 25 years I've owned/wrenched on Miatas I can only recall two times I've had this problem with a Miata.  Not to mention that OEM Mazda parts aren't anywhere near as crazy as BMW/Audi ones.

(1) I bought an insanely cheap timing belt kit from PartsGeek.  When I went to install the timing belt, I couldn't get it on.  I bought a name brand timing belt and had the same problem.  I eventually figured out the problem was that the mounting locations for the timing pulleys on the water pump had been machined more than an inch off!  It wasn't even close!  PartsGeek wouldn't take the part back, though I did win a chargeback fight.  It wasn't even about the money, it was about the hours of my life that they wasted.  Never buying from them again.

(2) I replaced an alternator with a reman unit from Advance Auto.  It had a free lifetime replacement.  I probably replaced it 12 times over the next decade.  Definitely not worth my time, and I'm never doing that again.

I've lost count of the number of crap parts I've bought for German cars, but I'm still not buying OEM at those prices.  I'm mostly coming out ahead.  I did have good luck with a $119 Mahle radiator and Gates hoses for the E30.  But I've suffered plenty of frustrations, and I'm glad to see I'm not the only one.

For a rad, I had very good luck with an NRF branded one (German company, they focus solely on cooling) I bought through work for my V8 swapped e36. I am probably going to order another one to have on hand as a spare for the drift car. 

Can learn more about the company here: NRF

It isn't just BMW - the issue of being unable to find factory quality parts for many makes is a tough one. There are many substandard parts manufactured, particularly in China and India and it drives the resellers crazy because one rub will be fine but the next one will be crap and unless you take ever point set or whatever out of the box and check or test it, your come-back rate is often unacceptably high.  OEM is definitely more expensive but also much more reliable.

This issue plagues the old British cars world too!

BMW branded stuff is priced to an insane level.  I will generally opt for the most expensive OE branded stuff that FCP euro sells, still generally half the price of the BMW stuff.  Only time it didn't really work out was (coincidentally) a DISA valve that started shedding some sort of rubber gasketing after just a year or two.  Might have had something to do with the oil in the intake, though.

I generally have good luck with parts fitting on the BMW, and on Mazda's.  It has ironically been my experience that nothing fits on old Chevy's though.  I mean really old, like 1966.

Berck said:

(1) I bought an insanely cheap timing belt kit from PartsGeek.  When I went to install the timing belt, I couldn't get it on.  I bought a name brand timing belt and had the same problem.  I eventually figured out the problem was that the mounting locations for the timing pulleys on the water pump had been machined more than an inch off!  It wasn't even close!  PartsGeek wouldn't take the part back, though I did win a chargeback fight.  It wasn't even about the money, it was about the hours of my life that they wasted.  Never buying from them again.

So the mounting locations on the engine were effectively changed and it's their fault it wouldn't fit? Am I misreading what you wrote?

In reply to z31maniac :

Miata and other Mazda B engine idlers bolt to the water pump.

Dorman used to be good, but anymore their stuff is a crap shoot. I bought a pair of control arms for my Falcon project that, when installed, would not pivot because they hit the bodywork on the inside.

https://youtu.be/d-DJlZL0EAU?si=U6w09jYkDCmGERCm

Turns out they are the exact same parts as Moog sells in their box. And they don't fit any better from a different box.

I bought my BMW parts from Pelican back in the day and never had a problem, but I know they've since been bought out.

Something to bear in mind is that when a retailer changes a parts line (from TRW to Moog, etc) they often will relabel or rebox the old line's parts with the new line's numbers/boxes.

So this is where you may see a lot of X company's parts in Y boxes.

The rest of the time, it is easier for brand X to buy Brand Y and put it in their boxes.  I have got a lot of Echlin with Mopar or Mercedes parts inside the box.

Berck said:

Since I just learned that FCP will actually take returns when they sell me crap, maybe I'll start buying more from them. 

They will replace anything you buy from them for as long as you own the car.  Definitely my go-to for the BMWs in the fleet.