Barry in St.Paul
Senior Member
freshly rebuilt ******, all Ford gears, best I could find out of several transmissions (Rev/1st and Reverse idler are NOS even..), excellent shafts, new bearings, etc... When I decelerate, like letting off the gas coming down a hill, I get a brief 'rattle' like the gears are free-wheeling. Thinking a thicker oil would help reduce this... I have the Bratton's "600W" oil, bought it about 5 years ago when I started rebuilding the ****** and engine. I've never thought it seemed very 'thick', vs what I've taken out of old transmissions or rear-ends. I've read many of the posts in the past and seems there is room for debate on whether the Model-A Parts vendors are supplying a true 600W or a blend of a lube with STP? (I think most recent was they DO add STP?) Anyway, since STP increases viscosity, debating about adding a little more to the ******. Is this 'rattle' on decel normal? (I've never driven a freshly rebuilt 'A before; my Dad's cars all have original trannys and the noises are kinda expected ;-)
Or, would one of the "best match" lubes, as listed by Marco at one point (Mobil:
Mobilgear 636, BP:Energol GR-XP 680, Castrol:Castrol Alpha LS680, Shell:Omala 680, Texaco:Meropa 680 ) be higher viscosity than the Bratton's 600W replacement? Which brings to mind a question, why wouldn't the parts suppliers simply buy one of the off the shelf lubes, if they are truly "equivalent" to the original 600W, instead of taking the trouble to make their own brew with STP?
thanks!
Or, would one of the "best match" lubes, as listed by Marco at one point (Mobil:
Mobilgear 636, BP:Energol GR-XP 680, Castrol:Castrol Alpha LS680, Shell:Omala 680, Texaco:Meropa 680 ) be higher viscosity than the Bratton's 600W replacement? Which brings to mind a question, why wouldn't the parts suppliers simply buy one of the off the shelf lubes, if they are truly "equivalent" to the original 600W, instead of taking the trouble to make their own brew with STP?
thanks!
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