

This is a special Core exchange option only.
We ship you a pair of E46 Bow Tension Cylinders from our inventory, and you send us back your old parts for a refund of your $300 deposit.
NOTE: If you have a 2003 model, we will need to know if your left bow tension cylinder has a detachable (clip-on) aluminum line fitting before you place your order
No sales tax for orders in the USA
We provide world class technical support
3-year standard warranty (should last decades)
This is a special Core exchange option only.
We ship you a pair of E46 Bow Tension Cylinders from our inventory, and you send us back your old parts for a refund of your $300 deposit.
See removal instructions https://www.tophydraulics.com/e46bowcylinders.pdf in our DIY section. You remove your cylinders you would like to have rebuilt, and send them to us. Core exchange (from our stock) is available ONLY for full sets of BMW cylinders. See removal instructions in our DIY section.
NOTE: There was a change in cylinder design in 2003, depending on country. Earlier model years have the detachable aluminum piece on the left side bow tension cylinder, which has the hydraulic lines permanently attached to it. This version is shown in the above picture. Newer model years have the hydraulic lines individually detachable from the left bow tension cylinder. In newer versions, lines 31 and 34 going to the valve block can be removed individually. Older and newer version bow tension cylinders (aka tension bar cylinders) are fully interchangeable as pairs, but not individually.
The right side cylinder always has the lines permanently attached, and the lines can be removed from the left side cylinder (clip on old version and T10 Torx bolt on new version).
P/Ns 54347025599, 54347025600
International shipping: One or two of these cylinders can be return shipped in an International Priority Mail or Express Mail Envelope (we box them up inside the envelope).
54347025599, 54347025600 |
Rebuild/Upgrade Service for your 1996-2002 BMW E36 Z3 Convertible Hydraulic Cylinder - send in your cylinder first for quick rebuild service.
Core Exchange option includes $200 Refundable Core Charge, and $50 surcharge for inventory management.
P/N: 54 34 8 410 307 aka 54348410307 or 54348407231
Z3 1.8
Z3 1.9 M43
Z3 1.9 M44
Z3 2.0
Z3 2.2i
Z3 2.8
Z3 3.0i
Z3 M3.2 S50
Z3 M3.2 S54
Price listed is for rebuild/upgrade service for an individual hydraulic hinge cylinder.
Expedited Core Exchange Option includes a $250 Refundable Core Charge plus a $75 surcharge for inventory management.
It is highly recommended to upgrade them in pairs. These hydraulic cylinders always fail almost simultaneously.
To order a pair of hinges instead, click here.
You send in your malfunctioning E88 1-Series hydro unit, and Top Hydraulics rebuilds it. The rebuild includes electric motor replacement or rewinding if necessary, two new high-current relays, service of hydraulic valves and solenoids, and upgrade of internal seals in the pump to eliminate current or future pressure loss or internal bypass. Three years warranty.
p/n 54-34-7171303 or 54347190715
This special core exchange option includes a $300 refundable core deposit, i. e., you pay $650 plus $300 deposit. These pumps have been rebuilt and upgraded. The electric motor has been replaced or rewound if necessary. Two new high-current relay have been installed, and all hydraulic valves and solenoids serviced. The internal seals in the pumps have been upgraded to eliminate current or future pressure loss or internal leak.
BMW 1-Series (E88 chassis) hydro unit/convertible top pump
You send in your malfunctioning BMW 2-Series (F23) hydro unit, and Top Hydraulics rebuilds it. The rebuild includes electric motor replacement or rewinding if necessary, a new high-current relay, service of hydraulic valves, and upgrade of internal seals in the pump to eliminate current or future pressure loss or internal bypass. Three years warranty.
P/N 54-34-7-421-753, aka 7310756, aka 541090, aka 54347421753
Rebuild/Upgrade Service for Right Tension Rod Cylinder for BMW E88 1-Series.
Send in your part(s) first, or select "Order now with core exchange" to order from our inventory. Core exchange orders are subject to a $50 inventory surcharge as well as a $120 refundable core deposit.
Replaced and improved rod seals, piston seals, cap seals, gland seals, wipers, and port seals make these parts better than brand new ones, with an expected service life of 30-50 years under normal circumstances.
P/N: 54347190668
Rebuild/Upgrade Service for the full set of BMW F23 2-Series.
Send in your cylinders first, or select "Order now with core exchange" to order a set from our inventory. Core exchange orders are subject to a $200 inventory surcharge as well as a $600 refundable core deposit.
Replaced and improved rod seals, piston seals, cap seals, gland seals, wipers, and port seals make these parts better than brand new ones, with an expected service life of 30-50 years under normal circumstances.
Top Hydraulics upgrades the seals in these cylinders with far superior material. It is highly recommended to upgrade the tonneau/case cover cylinders in pairs. You send in your cylinder(s) first, or order from our stock with the core exchange option below.
BMW P/N: 54348236956
It is highly recommended to upgrade the bow tension cylinders in pairs. You send in your cylinder(s) first.
Rebuild/Upgrade Service for Left Soft Top Lid Cylinder for BMW F23 2-Series.
Send in your part(s) first, or select "Order now with core exchange" to order from our inventory. Core exchange orders are subject to a $50 inventory surcharge as well as a $120 refundable core deposit.
Replaced and improved rod seals, piston seals, cap seals, gland seals, wipers, and port seals make these parts better than brand new ones, with an expected service life of 30-50 years under normal circumstances.
P/N: 54347421825
Package deal! Includes Rebuild/Upgrade of all 6 hydraulic cylinders and the hydraulic pump unit.
You send in your parts first and we will upgrade them to better than new condition, or choose the core exchange option and we ship from our inventory first.
Slightly extended version of the OEM hose, which is not available from BMW. Only available from Top Hydraulics. This line is for the newer version bow tension cylinder on the left side, top fitting, where the lines are attached via a screwed on clamp.
Rebuild/Upgrade Service for Right Main Lift Cylinder for BMW F23 2-Series.
Send in your part(s) first, or select "Order now with core exchange" to order from our inventory. Core exchange orders are subject to a $50 inventory surcharge as well as a $120 refundable core deposit.
Replaced and improved rod seals, piston seals, cap seals, gland seals, wipers, and port seals make these parts better than brand new ones, with an expected service life of 30-50 years under normal circumstances.
P/N: 54347421756
Package deal!
You send in your cylinders first; we will upgrade them to better than new condition. Optional core exchange has an inventory management surcharge, plus a $600 deposit.
Includes two main drive cylinders, two bow tension cylinders, and two tonneau cover cylinders.
Convertible hydraulic cylinder rebuild/upgrade for BMW model Z4 convertible soft top lifting system. Z4s have two "Convertible Hydraulic Top Hinges" with one built-in cylinder each. The price listed is per pair.
Optional core exchange is $100 more, plus a $400 refundable deposit, see details below. Core exchange is available only to US customers. The core exchange option is temporarily sold out.
Expedited Core Exchange Option where Top Hydraulics ships parts from our inventory first is $700 plus a $300 Refundable Core Charge.
These pumps have been rebuilt and upgraded. The electric motor has been replaced or rewound if necessary. A new high-current relay has been installed, and all hydraulic valves serviced. The internal seals in the pumps have been upgraded to eliminate current or future pressure loss or internal leak. Three years warranty.
P/N 54-34-7-421-753, aka 7310756, aka 541090, aka 54347421753