M52TU vs M54

M52TU vs M54

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Discussion

B234R

Original Poster:

85 posts

106 months

Friday 1st September 2017
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I have the chance to buy a one owner, manual 330i Touring E46 rather cheaply (although with 150,000 miles on the clock) and it´s very tempting. When new I´m sure that a 330i would be preferible to a 328i E46, it seems they drink petrol at the same rate and the 330i is faster. But now, knowing M52TU and M54 reliability weakness, which would be a better choice? I´ve heard oil consumption stories from the M54s, but I´m not sure if apart from PCV system there are other reasons.

Thanks..

Fox-

13,320 posts

251 months

Friday 1st September 2017
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I can't think of anything that would make an M52TU a better choice. The M54 is simply better and any downsides apply equally to the M52TU if not more so.

bmwmike

7,278 posts

113 months

Friday 1st September 2017
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M52tu and m54 are virtually identical IIRC

Huff

3,214 posts

196 months

Friday 1st September 2017
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That. And a CCV replacement (usu casue of oil consumption oddities) is easy, as are vac leaks to fix (the other common cause of modest irritations in throttle response) - and it's still an utterly lovely engine to drive. 'Reliability weaknesses' - utter BS. At that sort of mileage it's past easy/early failures and you simply need to take care of the whole via planned proactive maintenance anyway; there's nothing to choose between them and the parts are cheap, and the engines/systems very easy to work on. Nowt in it (and no excuse for neglecting it, given how easy these things make regular oil/filter changes and general maintenance)

If the car tickles your fancy and the price is right for overall vehicle condition - buy and enjoy.

Edited by Huff on Friday 1st September 22:17

Deptford Draylons

10,480 posts

248 months

Friday 1st September 2017
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I had an E36 with the M52 and gave up checking the oil in the end, it just never used any despite the fact the car was a 150k miles total beater and was about to be condemned due to rust. I switched to a E46 compact and M54 and it drinks oil. I did the CCV the other week so have yet to see if this will make any difference.
That said, the engine is very strong and very reliable, just needs topping up more often. I can't say its that big a deal and I wouldn't switch to an older chassis and the rust issues that go with doing just because of the increased oil consumption.

bmwmike

7,278 posts

113 months

Saturday 2nd September 2017
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M52 is not m52tu


M52tu is closer to m54 than M52. Different block and everything IIRC. I'm struggling to recall any differences between m52tu and m54.

Edit here we go, robbed from bimmerforums:


M54 has a drive-by-wire, M52TU has cable AND drive-by-wire (partially). There are some differences in the engine design, such as vacuum lines have a bit different way (also in the ETK these are not really correctly displayed since they used M52TU illustrations and adjusted them a bit). ECUs (MS42 for M52TU and MS43/45 based on model year for M54) are different, although they use quite similar electronics. DISA valve is different for both engines, too. So are the injectors. To say it completely correctly, the engines are similar in design, but way too different in many little things.

As mentioned, the M54B30 especially has the longest stroke which in time is causing the cylinder's ovality and at the end the higher oil consumption. The M54B25 is not influenced by this as much.


Edited by bmwmike on Saturday 2nd September 09:02

4rephill

5,059 posts

183 months

Saturday 2nd September 2017
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Deptford Draylons said:
I had an E36 with the M52 and gave up checking the oil in the end, it just never used any despite the fact the car was a 150k miles total beater and was about to be condemned due to rust. I switched to a E46 compact and M54 and it drinks oil. I did the CCV the other week so have yet to see if this will make any difference.
That said, the engine is very strong and very reliable, just needs topping up more often. I can't say its that big a deal and I wouldn't switch to an older chassis and the rust issues that go with doing just because of the increased oil consumption.
My previous car was a '97 E36 328i Sport with the M52 engine (Not the TU version), that drank a litre of oil every 300 miles. Compressions were all good, it didn't have any oil leaks, there wasn't any smoke on start up, and it only ever let out a bit of oil smoke right up at the red line.

My current car is a 2001 E46 330 ci with the M54 engine, and it doesn't use any oil at all - So what's your point? confused

The fact is, there are good and bad engines in both the M52 series, and the M54 series. Some use oil, some don't - It's pretty much pot-luck which you get.

I'd say that oil use or not, the 3.0L M54 engine is a lovely, torquey motor that suits the E46 nicely, giving it a satisfying shove in any gear due to the torque, and unless the price was exceptionally low, or you drive around like Miss Daisy is in the back, there's absolutely no reason whatsoever to choose a 2.8L E46 over a 3.0L - You'd just be missing out on a great engine.


And just as a reference, BMW used to classify using 1 litre of oil every 600 miles as being acceptable (I'm not sure if this is still the case on their more modern engines)

Sardonicus

19,073 posts

226 months

Saturday 2nd September 2017
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I am here to back the M54 motor although I did the CCV overhaul (preventative maintenance) i didnt previously & since fitting had any oil consumption woes 2.5 version @ 170k miles runs like a swiss watch biggrin

bmwmike

7,278 posts

113 months

Saturday 2nd September 2017
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I ran a m52tub25 engine to 178k and last i checked it was still MOT'd at 192k. It used no oil at all between oil services of 12k miles.

Very good engines indeed!

Put the later engines of n52 and n53 especially to shame ( I currently run a n53 f10 ) for reliability and over a long term even fuel consumption if you factor in the repair costs.




buggalugs

9,243 posts

242 months

Sunday 3rd September 2017
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I took my m52tu to 230k, and it's still going now at nearer 300 according to the MOT site. It had cam sensors and a radiator iirc. I think I'd rather have had the power of the m54 though assuming it wasn't an oil drinker.

g3org3y

20,897 posts

196 months

Sunday 3rd September 2017
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4rephill said:
My previous car was a '97 E36 328i Sport with the M52 engine (Not the TU version), that drank a litre of oil every 300 miles. Compressions were all good, it didn't have any oil leaks, there wasn't any smoke on start up, and it only ever let out a bit of oil smoke right up at the red line.
I'd suggest that the extent of your oil consumption on the M52 is unusual. I've had two M52 328s and neither used oil excessively. Absolutely no top ups required between oil changes/servicing.

4rephill

5,059 posts

183 months

Sunday 3rd September 2017
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g3org3y said:
I'd suggest that the extent of your oil consumption on the M52 is unusual. I've had two M52 328s and neither used oil excessively. Absolutely no top ups required between oil changes/servicing.
Actually, M52 Nikasil engines had quite a reputation for oil usage - M52 Alusil engines on the other hand were much better!

From: https://www.torquecars.com/bmw/nikasil-issue.php :

"Symptoms include a rough idle (which be attributed to a number of causes), uneven bore wear, loss of power, oil consumption rises dramatically and some M52s were known not to start in the cold"

Having discussed My oil consumption issues with BMW, they confirmed that the engine was the original Nikasil M52 unit, and suspected that it had been affected to a degree early in its life by the sulphur issue, and that I was now paying the price with the excessively high oil consumption.





g3org3y

20,897 posts

196 months

Sunday 3rd September 2017
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^Yes, Nikasil engines with issues/mild damage.

Sorry, I should have been clearer, M52s devoid of damage from Nikasil wear, shouldn't use oil.

My current 328 is an original Nikasil engine (bought on 126k, now on 194k) and doesn't use any oil. 1 litre every 300 miles is crazy amounts.

Edited by g3org3y on Sunday 3rd September 17:14

iSore

4,011 posts

149 months

Sunday 3rd September 2017
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The M54 was basically an M52TU with a fully electronic throttle body so it was compliant with optional DSC as well as a catalytic converter on both exhaust manifolds. The actual engines are near enough identical and interchange - the 2.5 certainly does and the 2.2 and 3.0 were just stroke changes on the previous 2.0 and 2.8.

Oil consumption is supposedly due to the thinner rings used on the M54. Some use oil, some don't but keeping the breather and its pipework healthy does help. Occasional water pump failure, Vanos seals etc. they're getting old now and the 328i is older still. With maintenance, they are an engine whose life span is indefinite and 200'000 miles plus is not only possible but common.

B234R

Original Poster:

85 posts

106 months

Monday 4th September 2017
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4rephill said:
My previous car was a '97 E36 328i Sport with the M52 engine (Not the TU version), that drank a litre of oil every 300 miles. Compressions were all good, it didn't have any oil leaks, there wasn't any smoke on start up, and it only ever let out a bit of oil smoke right up at the red line.

My current car is a 2001 E46 330 ci with the M54 engine, and it doesn't use any oil at all - So what's your point? confused

The fact is, there are good and bad engines in both the M52 series, and the M54 series. Some use oil, some don't - It's pretty much pot-luck which you get.

I'd say that oil use or not, the 3.0L M54 engine is a lovely, torquey motor that suits the E46 nicely, giving it a satisfying shove in any gear due to the torque, and unless the price was exceptionally low, or you drive around like Miss Daisy is in the back, there's absolutely no reason whatsoever to choose a 2.8L E46 over a 3.0L - You'd just be missing out on a great engine.


And just as a reference, BMW used to classify using 1 litre of oil every 600 miles as being acceptable (I'm not sure if this is still the case on their more modern engines)
Now I´ve got a 328i Touring E36, it used to drink 1 litre of oil every 200-250 miles. At the end we fitted a 528i E39 non-nikasil engine that doesn´t drink a drop of oil, even with fully synthetic Motul 5w40. When the mechanic dissasembled the old engine, he found that the cylinders were scratched...I don´t want to own another heavy oil drinker, that´s my main worry with the 330i.
Another worry is that a nice Alfa 156 V6 has appeared for sale, it´s in my budget, and I´ve heard that Busso engines use to drink a bit of oil...oh dear rolleyes

Spitfires

75 posts

85 months

Wednesday 6th September 2017
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I've had two 156 V6's, both very reliable (30k miles in a year in one of them). One drank oil, one didn't. Both looked after, no leaks and no smoke. Complete with Supersprint zorsts they sounded glorious. Only issue was the common MAF sensor dying. And myriad suspension components eaten.

My current 330Ci guzzles about 1/2 a litre every 1k miles but is a lovely engine also.

Richair

1,021 posts

202 months

Wednesday 6th September 2017
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Unless I'm mistaken, I can't believe this thread has run so long without someone mentioning the woeful throttle response on the M54 in the e46. I have diesels with better response!!.. But once wound up it is nicer motor to drive than a standard M52 due to the M54 pulling well between 4.5-6k where the M52 is choked by it's pea-shooter-esque inlet. An M52 with an M50 inlet would be the best of both worlds, but it seems that's a tricky mod to do these days due to the availability of donor inlets.

On the oil consumption thing: In my experience the M54 is a guzzler and the M52 doesn't use a drop. They changed to the oil control rings from a double pack with a centre spring, to a single ring and spring on the M54. There are various theories linking this to the PCV system and 'ring flutter' and there's actually a difference between the way the two PCV systems operate; the M54 is missing a vac line onto the PCV diaphragm that the M52 has, which is believed to be part of the problem. However the ports are actually there to instate this on the M54, which I've done on my 330ci and has helped lower oil consumption. I probably now see around .5 - 1l of use per 1k miles which on a 162k mile motor I don't think is unreasonable and is certainly inline with other peoples' experience. It's just something to keep an eye on.

Then there's the double vanos thing on the M54, but the seals should have been upgraded on most cars by now...

Both are decent motors and as long as (preventative) maintenance is kept on top of, they should do over 200k without bother.

Edited by Richair on Thursday 7th September 13:01

buggalugs

9,243 posts

242 months

Wednesday 6th September 2017
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Throttle was pretty slow on my m52tu as well. I never figured out exactly how it worked. It had a cable to it but also a motor on the side and the ECU had full authority over it for tc / dsc. The response felt quite damped anyway.

One thing I never got round to was looking at putting a 3.0 M54 inlet on the M52TU 2.8 as I read that it was a similar mod to doing the 325 inlet on the old 328 m52. Not sure what you do about the throttle though.

Spitfires

75 posts

85 months

Wednesday 6th September 2017
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Agree on the throttle response. My second 330 much better than the first and not so bad at higher RPM, but low revs it has a mind of it's own and is my biggest bugbear with the car.

B234R

Original Poster:

85 posts

106 months

Wednesday 6th September 2017
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Curious that, throttle response. A friend that owned a 328i E36 and a 330i E46 told me that throttle response was way worse in the 330i than in the 328i E36.

Throttle response in my 328i is nothing to write home about, years ago I had a Prelude VTEC and response was almost telepathic.