Coolant tank 1.2 bar (17.4 lb) cap upgrade
 

The X5 has been waiting for this upgrade. It's been out of stock for a while. After replacing the thermostat, I checked again. It was in stock. Ordered it Mon and it arrived yesterday. BMW sure uses a high pressure cap on older models. All new models are now a more industry standard close to 16-18 lbs. The new cap should provide time to fix other items before a coolant system overhaul. A new tank is ready to go on. The current tank is a replacement from marking. I won't know until it's replaced. I've read so many stores about plastic parts failures. Texas being a hot summer state, I think it's worth a try. It does have a new fan and clutch. The auxiliary fan is brushless for efficiency. I'll follow up on it when hot weather is here.


https://germanautosolutions.com/stor...r-coolant-cap/

Models with diesel engines have 1,4 bar expansion cap (17137639023). (On petrol engines 2,0 bar.)

I've invented a litany of new curse words trying to get the OE cap off over the years. Worst design in the world. Gave up and use a strap wrench every time. Thinking of this upgrade just for a more hand-friendly cap.

You won't be disappointed. The aluminum top is solid. Easy to grab. Better than carrying channel locks to open the stock plastic one.

I replaced my 2 bar cap with 1.4 bar cap from E34, M50 engine. Cheap alternative to the G.A.S. cap. I wanted to buy it but shipping to Canada was higher than the cap itself :)

interchangeable expansion tank caps? are all the same size?
 

Would that cap fit an expansion tank for a 3.0i M54 engine, like on my '01 X5? I like cheaper alternatives, where possible, though the aluminum cap is quite nice.

Yes it fits. I put one 1.4 cap on X5 M54 engine and another on E39 M52 engine.
I personally never had trouble unscrewing the plastic cap with my hands.

https://www.fcpeuro.com/products/bmw...ap-17111742232

Reutter is the OE mfgr. You used to be able to snag one on Amazon for under $20, but they no longer list them as available. Like everything else in this economy, it looks like the price has increased.

AM.

For $17 difference... I'll take that sexy one you posted X5chemist. Yeah, I like shiny things... you want to fight about it. ;)