Marine Help Centre

Got a Question? The answers to frequently asked questions can be found below. If you can't find the answer to your question please give us a call on the number at the top right of our Page or alternately send us an e-mail via the contact us page


Q: Is my gearbox mechanical or hydraulic?

A: Our PRM 60, 80, 90, 120 and 125 gearboxes are mechanical gearboxes. All our other marine gearbox models are hydraulic gearboxes.

Q: What Oil does my gearbox take?

A: A mechanical gearbox (PRM 60, 80, 90, 120 or 125) must use automatic transmission fluid (ATF) Dextron II or III

All hydraulic gearboxes must use mineral 15W40 (not synthetic)

Q: How do I check the oil level of the gearbox?

A: To check the oil level, the dipstick must be fully screwed down and a level can then be taken. DO NOT over fill your gearboxes as this is detrimental to their performance. If a mechanical unit is overfilled, then this will cause the clutch to wear out and the performance will continue to deteriorate.

Q: How do I know what gearbox and ratio I have?

Serial Number Plate

A: The serial plate on the top of the gearbox will say what model of PRM gearbox you have. 

The first line will have the serial number and the second line is the PRM model number and ratio.

An example of modern plates will say "280D2.5" which means that the gearbox is a PRM280 with a 2.5:1 ratio.

(If you have a red serial number plate then the gearbox ratio and serial number are stamped on the top of the plate.) 

Q: Oil is leaking from my gearbox. What do I do?

A: In most cases, this means that either a seal is damaged and needs replacing or there is a loose connection in your cooling circuit. It is best to call our Engineering department to discuss this problem.

Q: Is my gearbox still under warranty?

A: Our standard manufacturers warranty is 2 years, and starts from the date that the gearbox leaves our factory. If you are unsure of the age of your gearbox, please call or email our offices with the gearboxes serial number and we will be able to date your gearbox.

Q: What is the warranty procedure?

A: For our full warranty procedure please click here.

Q: Can I get a workshop manual for my gearbox?

A: Manuals for all of our gearboxes are available as PDFs from this site. These are available on the product pages. Click on the "user manual" to open a copy of the workshop manual.

For older gearboxes, the workshop manuals can be found here.