

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.
Send in your parts first, then we rebuild them, then we ship them back to you.
No sales tax for orders in the USA
We provide world class technical support
3-year standard warranty (should last decades)
Note that there is a significant amount of labor involved in removing and replacing (R&R) the hinges on a Z4 top, and that both hinges always fail (leak) at almost the same time. It is close to the same amount of labor to R&R both hinges compared to R&R of a single hinge. This makes it highly inadvisable to deal with only one hinge at a time. Top Hydraulics' rebuilds make your original hinges much better than brand new ones, on account of the far superior seals used. Usable service life expectancy of Top Hydraulics' rebuilt hinges should be over 30 years under normal circumstances, with a 3-year warranty.
For regular rebuild service, where you send us your hinges first, then we rebuild them, then we ship them back. Top Hydraulics may elect to use FedEx Express Saver instead if shipping to a business address. Shipping inside the US is only $15, and international shipping by FedEx International Priority is only $85 to most countries.
If you are in a hurry: domestic FedEx Priority Overnight shipping from Top Hydraulics via FedEx is only $55.
P/N's 54347193449 (left) and 54347193450 (right)
These hinges are actually very well made; only the OEM seals decay over time. Top Hydraulics replaces the leaking seals with material far superior to OEM quality.
For core exchange orders, where Top Hydraulics ships parts from its inventory first, then you return your old parts. the deposit is fully refundable if Top Hydraulics receives matching, rebuildable cores within a reasonable time frame. Core exchange is offered only in pairs, and core exchange cylinders ship exactly as pictured. In particular, this means they ship with the arms attached, but without the detachable mounting bracket (mounting bracket not shown in the photos - it is used to secure the interior trim of the car). Top Hydraulics recommends leaving the arms on the hinges, or it will be cumbersome to get the gear timing correct afterwards.
The rebuilt & upgraded cylinders (hinges) feature new and greatly improved rod seals, piston seals, gland seals, and port seals (where the hydraulic lines go into the cylinder). The service life should be at least 3 times as long as with the original seals, under similar circumstances.
In rare cases of excessive damage from previous DIY repair attempts or from someone forcing the top manually and bulging the cylinder housings that way, Top Hydraulics may refuse to work on your parts and refund your payment.
For shipping your hinges to us within the US, USPS Priority Mail Medium Flat Rate Boxes are a good choice. Be sure to package well, so that nothing gets lost in transit...
54347193449 and 54347193450 |
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.
Send in your part for for rebuild/upgrade service, or get immediate shipment from our inveentory if you choose optional core exchange.
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
Rebuild & Upgrade service for your BMW 5-Series (E61) Hydraulic Liftgate Pump. p/n 51247163661 (p/n printed on the pump is 7111867 and HB70401-002 or HB70401-001)
525xi, 528xi, 530xi, 535xi, 525xd and 530xd
Select "send in your parts first" for the $400 rebuild, or select "order now with core exchange" for a pump shipping from Top Hydraulics' inventory first.
Rebuild/Upgrade Service for the full set of BMW E88 1-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.
BMW part number 54348243269
Rebuild/Upgrade Service for Left Soft Top Lid 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: 54347190669
Rebuild/upgrade service (using best seals available ) for BMW convertible hydraulic lifting system. It is highly recommended to upgrade the main lift cylinders in pairs. Send in your cylinders or order from our stock with optional Core Exchange.
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.
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
You send in your malfunctioning BMW F12 6-Series hydraulic pump unit, and Top Hydraulics rebuilds it. The rebuild includes electric motor replacement or rewinding if necessary, service of hydraulic and solenoid valves, service of moving parts and replacement as necessary, upgrade of internal seals in the pump to eliminate current or future pressure loss or internal bypass, and extensive testing to ensure the pump exceeds factory specs. Three years warranty.
Core exchange option is available (we ship the part first from our inventory) for $50 surcharge plus $250 deposit. Core exchange pumps ship filled with fluid, for plug-and-play installation.
p/n: 54347299838
Early model years (cut-off somewhere in 2003) have bow tension cylinders aka clamping bar cylinders with hydraulic lines that cannot be removed from the cylinder. Send in your left side cylinder, and Top Hydraulics will replace the line with OEM material.
You send in your malfunctioning E63/E64 6-Series hydraulic pump unit, and Top Hydraulics rebuilds it. The rebuild includes electric motor replacement or rewinding if necessary, service of hydraulic and solenoid valves, service of moving parts and replacement as necessary, upgrade of internal seals in the pump to eliminate current or future pressure loss or internal bypass, and extensive testing to ensure the pump exceeds factory specs. Three years warranty.
p/n: 54347154648
Core exchange option is available (we ship the part first from our inventory) for $50 surcharge plus $250 deposit. Core exchange pumps ship filled with fluid, for plug-and-play installation.
Rebuild/Upgrade Service for Right Soft Top Lid 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: 54347190669
Special option: Core exchange. This means that you get a rebuilt & upgraded pump from Top Hydraulics' inventory first, then you ship back your original pump for credit of your $200 core refund. Top Hydraulics ships a pump as pictured: no mounting frame and no wiring harness, in order to keep the shipping cost low. You get a pump that has been rebuilt to outlast and outperform brand new ones.
BMW part number 54347025595, see more detailed notes below. Aka 54348234530. Number printed on the pump is normally 8 234 530.
Please make a special note in your order if you have a model year 2000 or 2001.
It is highly recommended to upgrade the bow tension cylinders in pairs. You send in your cylinder(s) first.