GuideFrom the workshop

Porsche Gearbox Leaking Oil

Oil loss at aged shaft seals is one of the typical cases on our workbench with the G50 and the 964 gearbox. After reconditioning, sealing is checked on our test bench, not assumed.

The typical case: aged shaft seals

Oil loss at aged shaft seals is one of the typical cases that land on our workbench with the G50 and the 964 gearbox. Even the best production gearbox is a case for the workbench after thirty years.

Rear axles and rear-axle differentials show the same picture: oil loss and play after decades without an overhaul frequently appear together there.

Why the full picture matters

Whether new seals are enough only shows at disassembly — before that, the condition of bearings, gear wheels and final drive cannot be judged. That is why a rebuild to factory specification does more than reseal: the gearbox is fully stripped, all bearings, synchromesh and shift elements are inspected, and the ring and pinion is set up. Every part is cleaned, checked and measured — only on that basis can anyone say what is really needed.

For rear-axle differentials — with or without a limited-slip unit — there is the fixed-price overhaul, including setting up the ring and pinion to factory specification.

Tightness is checked, not assumed

After every rebuild the gearbox runs on our test bench: all gears are shifted, the smooth running of the final drive is judged, sealing and noise behaviour are checked. Only then is it packed and shipped — ready to install, with photo documentation of the work and your replaced old parts.

The way to us: remove the gearbox and send it in — we take over from the binding quote after disassembly to the return shipment.

Common questions

01 Is it not enough to simply replace the seals?

A serious judgement is only possible after disassembly — before that, the condition of bearings, gear wheels and final drive cannot be assessed. After disassembly you receive a binding quote for what is actually needed — work only starts once you approve it.

02 How do I know the gearbox will be oil-tight afterwards?

Every reconditioned gearbox runs on our test bench before shipping — smooth running, shift quality and sealing are checked under real conditions, not assumed.

03 How do I get the gearbox to you?

Send it in removed from the car — drain the oil, secure the gearbox on a sturdy pallet or in a solid crate and ship it by freight or parcel service, with your name, phone number and a short description of the problem. All details are on our “Send in your gearbox” page.

Inquiry

What is on your bench?

Gearbox type and a few lines about your request — that is all we need for a first assessment. A photo helps but is not required. The answer comes from the machinist, not from sales.

Send inquiry

Reply usually within 24 hours — from the managing director himself, no ticket system, no call centre. We call back on request.

or directly: 06628 9159093 · info@antriebstechnik-schmidt.de