Hi I just had a double sendback with customer-supplied parts and I thought I'd make a thread containing peoples negative experiences with a defective part so that people avoid them in the future. I'm, Alpha European Autotech in San Jose and often people will bring parts to save money and well, cash in hand is always a good time.

Rein water pump, the spring retention clip for the coolant hose was not bent correctly from the factory, even when pushed in the hose would pop out within 50 miles, the water pump also made a particularly AWFUL noise in the morning which went away as you drove it, the casting was off, and it was just defective all around

Hengst carbon cabin filter, thin and flimsy compared to the Mann and Mahle unit for this car, it also blocks airflow. They also don't fit very well and are slightly large. I cannot recommend you avoid these enough, I'm a contrarian and I like to mix and match filters between Hengst/Mann/Mahle but for Mercedes they've really missed the boat.
These weigh less than half of what the much denser OEM filters weigh and are very flimsy. The kind of quality you'd expect to come from China, not Germany. It's well worth the money to go with OEM at 3x the price. These have no business in a high end German car.

URO/Moog suspension, absolute garbage suspension parts, bushings/ball joints often go bad within six months if not immediately, they're ok for cooling system parts, having often updated o-ring material that are an upgrade on BMW, and cooling fan replacements on a 20+ year old car have worked so far. BMW valve covers are a godsend since these things melt their own valve covers every 80k lol

Mobil 1 extended performance oil filter, they're made of paper and are rated to 20k but uh, I usually pull them out pretty twisted and mangled even at 10k and the o-rings sometimes don't even fit and I just throw the entire kit out and force them into a Mann filter. The filter material is incorrect, paper degrades much faster than the synthetic fleece material rated for synthetic oils.

Meyle brake rotors, they claim they're OE grade and high carbon and blah blah, but man compared to Pagid/Brembo/ATE/Zimmerman/Bosch these things get ROACHED within 6 months.

Autozone Duralast alternator/starters, man these things have like a 30% DOA rate with me so far. They're not even inexpensive, theyre just there for you if youre desperate.

Rebuild Master Tech RMT Airmatic struts, this company is particularly awful, DOA units, crappy warranty, the strut internals are often the ORIGINAL struts that haven't been rebuilt or inspected in any way despite being a brand new rebuilt unit with new air components. Arnott also is guilty of this but they're more thorough about their quality control, and for these cars there are NEW units which work probably even beter than the OEM Sachs/Monroe MB units. I've legitimately installed chinese/ebay/Aliexpress units that have yet to fail compared to these things floating around.

 

Nice and extensive post, I have also heard that you should avoid aftermarket spark plugs as well . I stick to OEM regardless of what those manufacturers claim

 

Actually about that, I do have data on spark plugs per all the sets I've been removing over the years from BMW and Mercedes, but specifically the mercedes:

Good ones:
Denso, NGK, Bosch, Mercedes Benz OEM (actually either Bosch OR NGK sometimes!). I'm currently using NGK Rutheniums, yes I am a double idiot for going aftermarket AND different plug design but I really never want to go back and do those plugs ever again, it's just not a fun service compared to fluids and filters for me. Mercedes Benz say 60k and you can honestly not see/perceive the difference but you can actually begin to wear down plugs as early at 40-50k! The ignition coils compensate for lower efficiency so you can ultimately go to 120k+ on original plugs if you really wanted to, but we're trying to be good to them. Rule of thumb I wouldn't really want to switch the kind of plug even though iridium etc last longer unless you want to experiment, as Hondas don't exactly have the spark energy requirements that a Mercedes does.

Ones to avoid:
Autolite, Champion (particularly the double plats), E3 or whatever

I would also advise most people look into replacing the ignition coil boots with the plugs, the little springs in them get rusty over time and it's bad for ignition, and its just nice to freshen up whatever you can while you're in there.

It's not about the strongest spark actually, it's particularly that the ignition coils are tuned to make a certain amount effort to ignite the plug, and you're not trying to "improve" anything you're just trying to keep things consistent.

Mercedes OEM plugs are expensive, so is their service its like $1000..

 

Such debates go for decades, but the truth is that you can't generalize them.
Obviously cheap part manufacturer is going to have lover parts life expectancy, but what would satisfy your demand?
Let's say Uro part will give you 7 years life for 1/5 price of OE part, that would give you 20?
I actually bought URO parts for 25 years old Mercedes and they work.
You don't want to put $5000 parts in restoring $3000 car.

 

I don't recommend OE parts most of the time, especially for brakes, plugs, air and oil filters, and fluids. It should be noted that the Mann CUK29005 filter is NOT the genuine filter, it's made at considerably lower quality.

There are other parts alternatives in-between that are easily as nice. URO is often not even cheap for what they are I'm going purely off what I've seen, customer sendbacks, defective parts I've removed, and not based on price or things I've heard. Compromising suspension components is a safety issue, it cooks tires prematurely when an undiagnosed parts fail before expected, as in the URO control arms, bushings. They do make nice BMW parts in terms of front drive accessories, coolant necks (yes BMW cannot even make a piece of pipe properly) that often can be better than genuine parts quality because of improvements in gasket design, but for suspension I've been watching this for like ten years. So even if the bushing hasn't cracked yet, you will have more flex than usual.

A Lemforder, Delphi, TRW arm will always be superior without being signifigantly more expensive than URO.

Actually theres a brand for control arms almost nobody knows about which have INCREDIBLE quality. They're carried by EEuroparts and ECS, called Sidem that are made in Belgium and they were 1:1 and felt great out of the box and in flex testing after installed. I have access to Mercedes Genuine same-day parts where I've looked at both side to side and chose the Sidem. At $75/arm for a forged aluminum arm, you're doing quite well for yourself. I use them in a 997S and they're very nice.

 

I had the same issue with aftermarket suspension parts not lasting, especially control arms and bushings. Fake Febi and sketchy Meyle stuff made it worse. I’ve had better luck trying to get used OEM parts through Ovoko—managed to score original arms that held up way longer than the new aftermarket ones I tried before.

 

Totally agree regarding the Mann oil filter! i couldnt believe how much worse it was when i was changing the oil for the first time on my 2013 e350. It had the OE purflux in it, and i never thought Mann would make something that much worse than OE since its literally the OE filter and only brand i get for all my porsche vehicles. I purchased 5 of those Mann filters for the e350, and unfortunately i dont think i will use them again. They didnt even have the same zig zag design the purflux has, and didnt sit properly in the housing (was a little loose).

I also got the Mann cabin filter, and was surprised how cheap it was compared to the other aftermarket brands, its always the most expensive for porsche's. turns out there was a reason for this too, the white locking slider did not fit and i had to reuse the OE one that was in the car. Cannot understand why Mann products are so bad for mercedes, is it just because they werent an OE supplier for these vehicles? I know purflux is the OE oil filter but what about the cabin filter?

Uro was always hit or miss for porsche as well, and id only get their stuff if it was the only option and if it was a part that wasnt important like washer fluid pump or something like that. Ive had great luck with Elring's products and got their Transmission service kit for the E350 and it was excellent, even came with new pan bolts for the transmission oil pan, and was priced incredibly cheap for what was in that kit. For anyone wondering about the p/n, i highly recommend it if you need to service your transmission soon. it is the Elring 620.160 kit for the newer 722.9 transmissions that take the blue fluid, and 620.140 for the older 722.9 transmissions.

My E350 recently had lesjofors rear springs installed, the original OE ones were broken on both sides. I hadnt heard of this brand before, but ive also never had a car that had the rear OE coil springs fail, but so far no issues with them. Does anyone else have experience with this brand? They were priced very well compared to the OE coil springs, and FCP had them so figured id give them a try and see if they hold up.

Anyway, totally agree with the statements above. I think each one of these aftermarket companies make good parts for some cars, and not so good for others. The key is figuring out what parts are the best for your vehicle, and not relying on any one, well known brand, even if you have had great experience with their parts in the past(especially if those excellent parts were for a different vehicle manufacturer than the vehicle you have now).

 

Interesting. I have been using the Mann oil, air and cabin air filters and think they fit great and seem to function the same. I have a 2010 W204 with M272 engine.

Once I was at the MB dealer getting some parts so picked up an oil filter while I was there and it was in a Star Parts box, the filter was the same exact filter as the Mann filter, even had Mann stamped on it next to the MB star logo.

Just last week I replaced my cabin air filter with a Mann filter, it was on Amazon for $15.99, still is.

Last fall I serviced my 722.964 transmission and use a Filtran filter. I had noticed Filtran is stamped on the Genuine Mercedes filters so searched around for more info. I compared the patent #'s off the Filtran website and they seem to match. Looks like they manufacture the filter materials have the patents on them. I found the Filtran filter with Elring gasket for $19.95 at https://www.idparts.com/automatic-tr...42-p-3726.html . Price has gone up since.

The filter fit on fine and the transmission seems to be running fine, thats all I can really comment on so far. If I have the car long enough to do another service i'll open the filter up and see what it looks like inside. The Filtran says made in China where the Genuine MB says Germany. Looks like Germany is IBS-Filtran.

 

Not sure if the p/n's for your car are the same as mine for the oil and cabin filter, maybe thats why your Mann filter's are better quality? Just wanted to mention that i thought it was funny that Filtran's best building is the one in China, haha. Made in china is no longer a bad thing...

 

I am in agreement with whoever it was that mentioned above, to use caution about generalizing that a supplier should be avoided because of specific issues.

When doing a service on my '14 E350, I also found that the Mann oil filter for the E350 fits very poorly. Fortunately, I also had a Purflux oil filter on hand, and was able to finish the service. But the reason I had bought the Mann for my E350, is because I had previously had excellent experience with Mann air, cabin and oil filters on my '07 SL550. Mann filters fit well, were well constructed, had quality filter media, and had equal or more pleats than filters from other brands, for that car.

Will I ever order another Mann oil filter for my E350? No. I would hope that Mann would have fixed the problem by now, but I'm not going to take the chance. Would I order a Mann filter for another European application? Without hesitation.