Oil radiator installation. Possible troubleshooting solutions?

[Alvaro.G]

Hello everyone! My name is Álvaro, I live in Spain, and as I mentioned in my introduction, I’ve been the owner of a Multivan T6 DSG 4Motion CXEC Generation Six for a year now. I imported it from Germany, and it currently has 140,000 kilometers. Apart from a minor blockage in the metal EGR pipe connection, which I resolved without any issues, I haven’t had any breakdowns. Also, the engine doesn’t consume any oil. I change the oil every 15,000 kilometers, and this year I’ve driven 40,000 kilometers with it.

However, I’ve noticed a concerning problem: at times, when maintaining a steady speed while climbing mountain passes (even those that aren’t very demanding), the oil temperature rises sharply, even exceeding 130 ºC. On relatively flat roads, the temperature stays between 100 ºC and 110 ºC.

After researching, I found discussions in German forums, like Red Head, about this issue. It seems to be a common problem attributed to oil degradation caused by high temperatures, which is also linked to the well-known failures in BiTDI engines.

My question is: has anyone here installed the Wagner oil cooler, like the one sold by JH-Parts exclusively for the T6? Does it really help control oil temperature? Or would it be possible to install a generic oil cooler?

I’m considering installing one, but I’m unsure if it’s really worth it. I’d greatly appreciate any advice or experiences you can share. Thanks in advance!

 

[CAB]

Hello.

I have no idea myself. But I would have thought that it would just be masking the problem.

 

[Alvaro.G]

Hola.

No tengo ni idea, pero pensé que eso solo estaría enmascarando el problema.

No lo tengo del todo claro. Es una pieza cara, ronda los 1.000€, pero una cosa está clara: dudo que sea bueno para el motor si la temperatura del aceite supera los 130º en determinados momentos.

 

[Bert69]

Hi @Alvaro.G - I also have the high oil temperature issue and found the German sites that mention poor thermal management with the BiTurbo engines that in turn leads to engine failure. I have a CXEB engine.
Hopefully someone else on the forum has experience they don't mind sharing.

 

[Alvaro.G]

Hi @Alvaro.G - I also have the high oil temperature issue and found the German sites that mention poor thermal management with the BiTurbo engines that in turn leads to engine failure. I have a CXEB engine.
Hopefully someone else on the forum has experience they don't mind sharing.

Hello, my engine is also CXBE. I’ve noticed that this issue is more controlled during winter, but my advice is not to keep the oil for more than 15,000 kilometers. I’m also using an additive (Moligen Motor Protect), and I believe this helps as well.

 

[Minaei]

Hello everyone! My name is Álvaro, I live in Spain, and as I mentioned in my introduction, I’ve been the owner of a Multivan T6 DSG 4Motion CXEC Generation Six for a year now. I imported it from Germany, and it currently has 140,000 kilometers. Apart from a minor blockage in the metal EGR pipe connection, which I resolved without any issues, I haven’t had any breakdowns. Also, the engine doesn’t consume any oil. I change the oil every 15,000 kilometers, and this year I’ve driven 40,000 kilometers with it.

However, I’ve noticed a concerning problem: at times, when maintaining a steady speed while climbing mountain passes (even those that aren’t very demanding), the oil temperature rises sharply, even exceeding 130 ºC. On relatively flat roads, the temperature stays between 100 ºC and 110 ºC.

After researching, I found discussions in German forums, like Red Head, about this issue. It seems to be a common problem attributed to oil degradation caused by high temperatures, which is also linked to the well-known failures in BiTDI engines.

My question is: has anyone here installed the Wagner oil cooler, like the one sold by JH-Parts exclusively for the T6? Does it really help control oil temperature? Or would it be possible to install a generic oil cooler?

I’m considering installing one, but I’m unsure if it’s really worth it. I’d greatly appreciate any advice or experiences you can share. Thanks in advance!

I just ordered this part and I am going to install it, My engine is DMZA, T6.1 204 Hp, 2021. I have the same problem, over 100km/h the oil temp rises up to 130.
Although all the official services confirm it's not a problem I think the oil itself at a higher temperature will lose its task but I am curious what is the oil pressure at this temp.
I will post later on about the result of installation

 

[Cog Head]

How did you guys get on fitting the oil coolers?

I’ve got the front off my van at the minute, If the coolers make a noticeable difference, I’d like to get it done before I out it all back together

 

[Marc R]

Nice feature, there are several options online for oil coolers.

Does the 2.0 BiT TDI CFCA work with a sandwich plate for an external oil cooler?

 

[Cog Head]

Forge motorsport do a kit for way less than the Wagner kit.

They all have a take off plate that goes in place of the existing oil/water labyrinth type system, which are always going to be prone to blockages, closely followed by a turbo replacement bill

 

[Marc R]

Unfortunately there is no other way for the CFCA, driving with consistently high oil temps isnt very good either....

 

[Cog Head]

What system do you have fitted?

 

[Marc R]

Nothing yet but looking into the Darkside developments kit, going to order tomorrow.

 

[Cog Head]

I’m working on pricing up a kit using the forge take off plate, AN fittings and a wide similar sized cooler to the Wagner unit.

 

[Cog Head]

So you can put a kit together yourself for £471.58

Forge take off plate
Serck Motorsport oil cooler
Serck Motorsport M22 - AN-10 fittings
Braided oil pipe & fittings

 

[Richard T6.1]

Any system should be thermostatically controlled or the cure can easily be as bad as the disease.

Hello everyone! My name is Álvaro, I live in Spain, and as I mentioned in my introduction, I’ve been the owner of a Multivan T6 DSG 4Motion CXEC Generation Six for a year now. I imported it from Germany, and it currently has 140,000 kilometers. Apart from a minor blockage in the metal EGR pipe connection, which I resolved without any issues, I haven’t had any breakdowns. Also, the engine doesn’t consume any oil. I change the oil every 15,000 kilometers, and this year I’ve driven 40,000 kilometers with it.

However, I’ve noticed a concerning problem: at times, when maintaining a steady speed while climbing mountain passes (even those that aren’t very demanding), the oil temperature rises sharply, even exceeding 130 ºC. On relatively flat roads, the temperature stays between 100 ºC and 110 ºC.

After researching, I found discussions in German forums, like Red Head, about this issue. It seems to be a common problem attributed to oil degradation caused by high temperatures, which is also linked to the well-known failures in BiTDI engines.

My question is: has anyone here installed the Wagner oil cooler, like the one sold by JH-Parts exclusively for the T6? Does it really help control oil temperature? Or would it be possible to install a generic oil cooler?

I’m considering installing one, but I’m unsure if it’s really worth it. I’d greatly appreciate any advice or experiences you can share. Thanks in advance!

I think Red Head is your best bet for shure. Very few companies have as much experience and knowledge about Transporter TDIs as they have.

When I read the marketing blurb on sites like Wagner about ‘competition this and that’ (a utility van… ), throwing percentages around with no relevance whatsoever etc. I get itchy the wrong way.

 

[Cog Head]

I totally agree! Especially in winter.

Does the engine not have a thermostat?
With the take off plates, you’re replacing the water/oil cooler with an air/oil cooler, no controls have been changed, plus you can fix a remote oil thermostat if need be.

 

[Cog Head]

I believe the engine oil thermostat is within the oil filter housing, which is also a front off job, so it looks like I’ll be replacing that while I’m in there, as the van has done 117,000mi the stat may also be causing high oil temps too.

 

[Richard T6.1]

I’m not sure but I think an oil cooler needs it’s own thermostat, only providing extra cooling when needed. Ideally it should keep the oil temp hovering around 115C max. This is also how Red Head does it.

Modern synthetic oils can ‘cope’ with 130C temps but what is usually not told is that the oil ages and deteriorates fast above 115C. Combined with the long oil change intervals, this creates kind of a toxic mix that makes the BiTurbo’s so vulnerable causing so many engine problems/failures (besides faulty EGRs on earlier models). They tend to run too hot in general on oil that’s in there too long and has lost a lot of it’s initial properties after 10-12 K KMs. The (huge) German TX forum reads like a permanent horror show on this topic.

My ‘24 150 (DNA) doesn’t suffer from high oil temps, 115C is the highest I’ve ever seen to date. But I still change the oil & filters after every 10-12 K KMs. I have the oil temp permanently selected on the dash. These engines also take quite a while to get up to temperature btw.

 

[Sasquatch]

Yes, the take off plates have their own thermostat and they're usually fail-safe, so a failure of the valve or increased back pressure from a blockage leaves the valve to the closed position and maintains correct oil flow via the filter.

It goes without saying that such items from the likes of AliExpress are unlikely to be so diligently designed.

 

[Cog Head]

The only take off plate I can find with its own thermostat seems to be the Wagner unit.
The forge unit doesn't have one, its simply a plate with two M22 outlets, I believe this is the only place we can intercept the oil flow, so if I replace the original liquid to liquid heat exchanger (which is slowly rotting from being exposed to exhaust gasses and coolant) with an air to liquid heat exchanger (front mount oil cooler) whatever was controlling the oil temp and flow before will continue to do so...

Are there any drawings showing the oil system on the CXEB engine? id like to see where the oil thermostat actually is.

My CXEB 204 runs at around 100 with normal driving, with some spirited driving or the caravan on the back, it hikes to over 120, i too have the oil temp permanently on the MFD, when it raises to over 115 I usually find a way to reduce engine load.

You can see the aluminium degrading in the bottom left corner, I REALY don't want this to blow through into the coolant or oil passage ways while I'm in Europe next year.
I can replace this original underperforming unit with another, or I can spend the same money on a front mount oil cooler kit as above.