Personnellement j'utilise de l'huile d'une viscosité SAE 20W50
Le grade de huile c'est une chose, mais il y aussi le pourcentage de Zinc dans l'huile qui est important pour nos anciennes. Il faut que le taux soit le plus elevé possible.
Éviter les problèmes en choisissant la bonne huile qui a une teneur en zinc d'au moins 0,11%. Si vous utilisez de l'huile à zéro teneur en zinc dans un vieux moteur, ca peut etre tres problematique
Voici une liste d'huile avec les pourcentage de zinc

En anglais
API service guide
http://www.api.org/certifications/engineoil/pubs/upload/EngineOilGuide_March2010.pdfI've been hearing about way too many camshafts going flat nowadays-- particularly on freshly built motors using flat tappets.I've been hearing about way too many camshafts going flat nowadays-- particularly on freshly built motors using flat tappets.
Zinc has been added to oil for years as an anti-wear additive-- particularly crucial where there is metal to metal contact in the engine-- ESPECIALLY flat tappet to camshaft contact.
Today, flat tappets dont exist in most new cars. Today, emissions has pressured oil companies to remove zinc from oil. So, a necessary component for older cars has been going away.... BEWARE.
BOTTOM LINE: Running an old engine without zinc in the oil is bad news-- especially when breaking in a fresh build. Ask around and you'll hear about high rates of camshafts going flat. Avoid the problem by choosing the right oil-- that has a zinc content of at least .11%. If you're running zero zinc content oil in an old engine, I believe you're asking for trouble.
I've done some research. Here is the zinc content of todays oils:
20W-50
AMSOIL (old) none
AMSOIL (new) none
Castrol GTX .12
Exxon High Performance .11
Havoline Formula 3 none
Kendall GT-1 .16
Pennzoil GT Perf. none
Quaker State Dlx. none
Red Line none
Shell Truck Guard .15
Spectro Golden 4 .15
Spectro Golden M.G. .13
Unocal .12
Valvoline All Climate .11
Valvoline Turbo .13
Valvoline Race .20
Valvoline Synthetic .12
20W-40
AMSOIL none
Castrol Multi-Grade .12
Quaker State none
15W-50
Chevron .11
Mobil 1 none
Mystic JT8 .15
Red Line none
5W-50
Castrol Syntec .10
Quaker State Synquest none
Pennzoil Performax none
5W-40
Havoline none
15W-40
AMSOIL (old) none
AMSOIL (new) none
Castrol .14
Chevron Delo 400 none
Exxon XD3 .14
Exxon XD3 Extra .13
Kendall GT-1 .16
Mystic JT8 .15
Red Line none
Shell Rotella w/XLA .13
Valvoline All Fleet .15
Valvoline Turbo .13
10W-30
AMSOIL (old) none
AMSOIL (new) none
Castrol GTX .12
Chevron Supreme .11
Exxon Superflo Hi Perf 135 .11
Exxon Superflo Supreme 133 .13
Havoline Formula 3 none
Kendall GT-1 .16
Mobil 1 none
Pennzoil PLZ Turbo none
Quaker State none
Red Line none
Shell Fire and Ice .12
Shell Super 2000 .13
Shell Truck Guard .15
Spectro Golden M.G. none
Unocal Super .12
Valvoline All Climate .11
Valvoline Turbo .13
Valvoline Race .20
Valvoline Synthetic .12
5W-30
AMSOIL (old) none
AMSOIL (new) none
Castrol GTX .12
Chevron Supreme .11
Chevron Supreme Synt. .12
Exxon Superflow HP .11
Havoline Formula 3 none
Mobil 1 none
Mystic JT8 .1
Quaker State none
Red Line none
Shell Fire and Ice .12
Unocal .12
Valvoline All Climate .11
Valvoline Turbo .13
Valvoline Synthetic .12