n52 longevity
 

Now that there seems to be a buyer for the s4, I need to think of my upcoming bmw. Still not decided between e46 & e90 but leaning towards the latter. I even started thinking of euro delivery as the stars seem to line up...

I have unused vacation, I will be buying an xi, we have a couple of cars to get us through a couple of months. The weather is a big if, but then I might go skiing in the alps. If I get serious about it, that'll be a separate thread.

One thing I'm wondering about is n52 longevity (the 100-200k miles kind that I haven't been getting to since my student days :eeps: ). I've owned two m54's and an m52tu and I trust them both highly. The m52tu does have a stall loop (but it's not really a mechanical fault and I'm confident it will go long). The m54 is also a bit finicky at idle (especially in zhp form) but seems rock solid.

The idea of a daily driver engine that can see 150k with oil changes (and hopefully no timing/valve work) is very attractive to me. The n52 block is magnesium/aluminum. I'm sure bmw tested this extensively but then again fancy alloys worry me... Any thoughts?

I have to say that if I had to choose between betting that (a) an N52 won't need major repairs before 150K miles, and (b) you won't keep the car anywhere near long enough to ever have to worry about it, I would have to go with (b).

The short answer to your actual question, though, is that there aren't enough N52s with high mileage yet to really answer the question. How long with the Valvetronic parts last? Are there going to be any major cooling system issues? Are there going to be major problems with the electronics? Are there going to be weird issues that arise from the AL/Mg block?

Possibly, but it's hard to say yet. If I were you, I wouldn't worry about it. The chances you'll keep the car long enough to find out are minimal, and if it turns out that there is some sort of horrible problem you can always unload it. Actually, assuming that the lease programs are still solid, if I were you I'd do ED on a new one and lease it.

I alluded to as much that my habits keep me away from the 100k+ zone.. But I'm really getting tired of changing cars and like the idea of something that dependable even if I never end up seeing that mileage. You clarified the possible issues, most of these are carryover, like valvetronic, cooling (a perrenial bmw favorite) and electronics.

The one that concerns me most is the Al/Mg block mating. I feel like the heat cycling/10-yr down the road behaviour of this is pretty hard to test. Mg is just a scary metal to deal with.

I believe that there are a few N52s at E90Post with 75,000 + miles. You might want to search around over there.


The Al/Mg block is worrisome.

But that's not why you're selling?

SG is not my top choice, but if you had an xi with folding seats, we'd probably have a deal.

I'm hoping it does okay. It's the engine in my 530xiT.

I guess I'm being silly - there are hundreds of thousands of these engines running around the world.

concur.