M5 specific parts and availability in 2024

[Technician117]

Hey guys,

I've been lurking and reading A LOT the last 3 months since buying my first e28, an M5. I've been able to figure out a lot of things from all this reading, but there are a couple items that are "current times" related. By that I mean since this website is more a repository than highly active community, current parts availability isn't discussed very much.

I've actually been pleasantly surprised by the amount of parts that are still available from BMW. Honestly, we should be thankful considering it seems like everyday one more part goes NLA for my e39 M5's... cars that are 12 years newer!

Anyway, in my quest to get this 88 M5 running better (and then perfectly), I've had to look into some parts that are either NLA from BMW or cost prohibitive to buy from them versus an aftermarket alternative. Case in point, I'm considering replacing the fuel injectors with rebuilt units (not just cleaned and flow tested) since mine likely have 323,000 miles on them. Despite a 2-3" thick folder of records, I don't see the injectors having been replaced before. I found Standard Motor Products sells a remanufactured injector, # FJ11. Does anyone have any experience with them, or a different suggestion for a replacement injector?

Next, the radiator. Mine appears to have started leaking, which sucks because this one is 12 years old but only with about 25k miles of use. From my searching, you can buy one from BMW for $550. I'm struggling to find an aftermarket radiator (in stock) from the likes of Behr (Mahle/Hella these days) or Nissens. I'd like to stay with a stock radiator, but see I could go all aluminum. Nice to see that performance support is still out there as well. Is there a difference between the M5 radiator and say a late model 535is manual? RealOEM lists 17112226018 as the M5 radiator part number with fitment listed as: 11/86 - 11/87 5 series and 7/86 - 9/88 6 series but didn't specifically say M5/M6. Thoughts?

Thanks in advance!

[austin8753]

would highly recommend having your original Bosch #201 injectors reconditioned. an outfit, local to me in Clackamas, Oregon, offers 24 hour turnaround from time of arrival - Injector Masters. the aftermarket injectors pale in quality, compared to the original units.

the 535is inlet/outlets terminate in the incorrect positions for the M5, so no, they aren't compatible.

[Technician117]

Thanks for the info. Rebuilding my injectors is still on the table. For what it's worth, the ones I was looking at say they are "reconditioned" not brand new aftermarket. Rock Auto lists GB remanufacturing as well (with a core exchange) but they only list 3 "in stock" from GB so I'd still have to send mine in for the work anyway. Better off using a smaller company like the one you mentioned in that case.

I guess I'll have to pony up for the BMW radiator. I'll probably pay the premium to go through FCP Euro as well and keep my fingers crossed they don't totally discontinue making them before I need another one!

2 more parts I just thought of for replacements as well:

ignition coil - I'd really like a Bosch unit. Right now I have a dying Bosch that was on the car that I replaced with a China aftermarket from the autoparts store. It's working fine, but I'm wondering what part number crossovers would work from other BMW's of the era? (for a Bosch unit)

idle air control valve - BMW is NLA, NOS is ridiculously expensive but I see aftermarket ones for cheap. I just cleaned mine and siliconed around the connector (it was leaking when I smoke tested the intake). Just keeping my options open for the future. Any specific ones to look for?

[Randomg]

Bought mine from five0 motorsport. They used to rebuild the old ones but now just offer their own. I appreciated all the details they gave for purposes of potential future megasquirt install (dead time vs voltage, flow rate per injector, actual impedance, open time). If you go with them, I'd insist on ones that actual output 261 cc/min, since mine all were flow matched to around 253.

[milarsky]

When I had to replace my radiator, I ponied up for the Wizard Cooling all-aluminum radiator. It was an exact plug-and-play. I know that Austin is working with CSF Radiators and Cooling and will produce a new M5 e28 radiator very soon. I think it is being released very shortly. So you do have a few choices!

[Fanclutchnut]

I can report back on those rock auto injectors. We ordered one recently to replace our bank 6 injector, which was stuck. We installed it and it worked great. It is a Bosch BMW rebuilt unit. We plan on sending our injectors out to hurst injection to be rebuilt, but wanted to drive the car until we enter the next phase of the project.

In December we’re going to remove the rear subframe rebuild it and replace the hard brake and fuel lines. I’ve been tracking the prices of items such as air filters, rear differential mounts, rubber fuel line and the end tank pump. All of them seem to have random exorbitant pricing.

I can kind of accept the scarcity of some of these things, but the random pricing that seems to go along with the ones that are still available irritates me.