Engine oil, again sorry.

Hurth gearboxes fitted to Thornycroft engines have always used ATF and ZF gearboxes have very similar design and are replacements for Hurth. The hand books for my Hurth gearboxes specify ATF and I believe the same applies to the ZF replacements.

Ref the ZF website http://www.zfmarineparts.com/ which specifies ATF

6.1.4 FILLING UP WITH TRANSMISSION FLUID
Fill with ATF oil for automatic gearboxes
according to the indicated quantities.
Add the quantity considered necessary
for filling the heat exchanger
and relative connection pipes.
ZF 4-1 M: ........ 0 US-qts (0,30 liters)
ZF 5 M: ............ 0 US-qts (0,30 liters)
ZF 10 M: .......... 0 US-qts (0,35 liters)
ZF 12 M: .......... 0 US-qts (0,55 liters)

ZF10 = HBW100
 
I have read up on all the threads about the correct engine lube oil to use in my Perkins perama. The manual says to use a API CC/SE or API CD/SE , most of the websites say these are obsolete...I have read vyv coxs excellent site on lube oil, but I am still confused.

Could someone please tell me in layman's terms the type of oil i need please. Thanks.

I literally just decided to change all mine from bog standard 15/40 CF4 to Morris 10/40 API CC on the recommendation of Vyv and other advice. My Perkins from a 1996 boat asks for the same as you... CC or CD at 15/40. These engines were in many things working hard. For a boat, especially a sailing boat I think 10/40 is better given that a lot of motoring is on a cold engine into and out of harbour.
 
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