Rein BMW Coolant Expansion Tanks for BMW 5 Series E34 (1987-1995)

Clear BMW chassis

Please ensure your correct model is selected

On certain models, namely E36, E46, and E90, the factory BMW expansion tank is prone to either breaking at connection points or blowing apart altogether. If you're starting to feel like your expansion tank is on borrowed time, it's probably time to replace with either a direct OE replacement, or strengthen your cooling setup with an aluminum expansion tank - we offer numerous performance upgrades for your expansion tank. Especially if you're someone who likes to track your BMW, we recommend upgrading your expansion tank to avoid ruining your track day.
Sort By:

OEM Rein Expansion Tank Cap - BMW E32 E34 E36 E38 E39 E46 & More ...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:340541
Part#: 17111742231
In Stock
$ 17.99 USD
Free Shipping on orders $49 and up
This radiator expansion tank cap is used most BMW's from 1991-2006. It is a common failure item. When this item fails, it cannot hold pressure which results in your BMW overheating. If you are overhauling your coolant system, now is the time to consider preventative replacing this cap. It is also referred to as the coolant reservoir cap.
Show More Show Less
Rein Expansion Tank Cap - E30, E34
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:592018
Part#: 17137639023
Ships in 3 Business Days
$ 14.99 USD
Free Shipping on orders $49 and up
$ 14.99 USD
Free Shipping on orders $49 and up
1.4 Bar pressure
Coolant Expansion Tank With Cap - 17111712835
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Rein - Corporate Logo
T#:46616014
Part#: EPK0012
Back Ordered
$ 29.99 USD
Free Shipping on orders $49 and up
The coolant expansion tank provides a place for excess fluid as coolant expands and contracts with temperature changes. Constant exposure to these extremes can cause the tank to crack, break, or suffer damage to its nipples or mounting points. To keep your cooling system sealed and functioning properly, any damaged tank should be replaced.
Show More Show Less