An interesting discovery about the E38 auxiliary fan

[voodoomelon]

So my E38s auxiliary fan gave up, it only tried to spin like in Edwin's video and never started a full rotation.

The fan in question is for E38s year 09/98 onwards. Dealer price was €450 + tax.
The reason it's so expensive is that it is a CANBUS controlled fan; it takes readings from the ECU regarding coolant temperature, vehicle speed, aircon settings etc and bases the fan speed on these parameters. There is a host of electronics in the fan hub, thus increasing the price.

Anyways, I found it extremely difficult to find an aftermarket fan for the E38, the part number for ALL E38s, 725, 728, 735, 740, 750 from 09/98 onwards is: 64546919053.

There are a few aftermarket options available in the USA apparently, but hard to find elsewhere. The only one I found was in Germany and was €300 + tax and shipping, not too cheap.

So I took a gamble.

I ordered an aftermarket E39 fan, part number 64546921395. This fan is for 520, 523, 530, 535, 540 and M5 models, from 09/98 onwards.

I deduced that if the old two-speed fans for both the E38s amd E39s ended in 08/98, they must both be the same. Worst case the shrouds wouldn't fit and you can simply swap just the fans themselves.

Why is all this important?

There are bucketloads of E39 fans available, new, used, OEM, non OEM, a much, much larger selection. I picked up an brand new aftermarket one for just over €200 shipped.

Arrived by courier, plugged it in for a quick test and voilá:


It turns out that the ONLY difference between the two setups is that the fan shroud on the E39 model has one inlet flap less on the top left of the unit:


Apart from this, they are essentially exactly the same. The mounting holes line up no problem, the power plug is the same and the depth of the shroud is the same. It simply pops into place!

To combat the reduced airflow of the E39 model, I simply cut the corner off that had no inlet flap:





Here's a video of it in action:

http://youtu.be/8gfPW-YOZ40?hd=1

Hope that helps someone out.

[SEVEN40iL]

Good research!

[TxDarth]

I wonder if it is a high failure item like it is on our e38's....

I bet it is - can't see any difference in the fan part itself.

Good info as I am in need of one as we speak and I have been too cheap to buy one.

[psjr]

Great find!
This will help a ton of people with post-facelift E38s.

[voodoomelon]

I'd say they fail just as frequently in the E39 models.
What annoyed the hell out of me was the amount of different part numbers for this unit, I must have come across 8 different ones, including the 2 stamped on my unit, which my local dealer didn't even recognise.

It got to the stage where I just had to take a chance to avoid a big bill and it paid off.

[whitebread740]

Thats good to know now, I spent $425 last year on a new one through BMW and that was my cost through my work, not sure if its bmw's cost on the part. But I think it was listed ~$600 msrp if I had gone to BMW myself.

[voodoomelon]

I'd well believe they're up around $600, damn expensive units.

[whitebread740]

I know, it sucks. Plenty of pre 98 units for under $300, its a good but bad thing to have a late model.

[IcemanBHE]

Good job.

But I probably wouldnt have cut the shroud.

I live dangerously.

[voodoomelon]

I was going to Dremel a little hole instead, but it stopped working on me the other day. If it remains covered up, its quite a large area not getting any airflow.

[TxDarth]

I just looked up the difference on real OEM base

for my car '01 e38 - cost is shown to be 510.00 pn 64546921383

for an '01 e39 530 - cost is 375.00 pn - 64546921395

[740iSport303]

I just looked up the difference on real OEM base

for my car '01 e38 - cost is shown to be 510.00 pn 64546921383

for an '01 e39 530 - cost is 375.00 pn - 64546921395

Tischer/Getbmwparts.com Prices plus shipping.

64546921383 - $455.10

64546921395 - $332.20

Quite a difference!

[das borgen]

ahh,..... you have a M52TUB28

great motor

aside from oil separator valve, not much else goes wrong on it

[voodoomelon]

Yup, 4.5 years now and 103k miles, never burnt 1ml of oil and is smooth as silk. Never a seconds trouble.

[Sroor9001]

Hi sorry for raising old thread but my fan pwm controller burned not working any more so it was external just cut it and hot wired to work when I switch on ac
In my country I have a lot of e38 in scrapyard but just little e39
So I mean I can go to aux fan from e38 and fix it in my car my car is 520i model 2002
Cause e38 fan got 4 wire pin but e39 got 3 wire pin but all are same socket so is it interchangeable ??
Hope some body reply

[Dan750iL]

How hard did it look like it would have been to swap the fans and just reuse the original shroud?

[xboss]

I was going to Dremel a little hole instead, but it stopped working on me the other day. If it remains covered up, its quite a large area not getting any airflow.

I deduce it's not really a dremel then. A dremel type rotary tool right?

Just saying that dremels are high quality.

[Sroor9001]

E38 has 3 or 4 wires ? Cause e39 has 3 wires want to buy e38 fan and install it in my e39

[purplecty]

How is the quality of this fan? Have any issues? Still working properly?

[TxDarth]

E38 has 3 or 4 wires ? Cause e39 has 3 wires want to buy e38 fan and install it in my e39

If you are buying new the e39 fan is cheaper than the e38 PWM fans. By almost 100.00 as priced a year ago. And I know the e39 fan will fit the e38. The shroud are slightly different - the e39 shroud has one corner that is different. The e38 has all four corners the same.

The fans themselves can be interchanged on the shrouds....

At one time you could buy just the fan motors from BMW but they changed that some years ago.

[purplecty]

http://www.ebay.com/itm/281801111170

Im buying one

[TxDarth]

I don't know if I will need it but I bought one too. I can change the fan, motor to the e38 shroud............

[purplecty]

I'll just put mine In as is. We need to get you INPA running so you can acticate the fan manually...

[TxDarth]

I'll just put mine In as is

The shroud's are not the same - notice the one corner has a notched area the e38 does not.

[srq]

I'll just put mine In as is. We need to get you INPA running so you can acticate the fan manually...

How do you activate the fan w/INPA?