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What is the proper oil for Bugeye engne and transmission

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M

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I know this question has probably been asked here a hundred times, but I can't find a relevant thread so I though I'd ask again. Please bear with me.

The workshop handbook for the Bugeye Sprite calls for 20W30 (conventional) oil for both the engine and the transmission. (This is quite different for other LBCs like the TR3, for example).

But from what I keep reading, 20W30 is generally described as a gear oil (?) and it is hard to find in local stores. Some say it can scratch internal engine parts (??) and causes trouble for the oil pump.

A number of people have told me that they use 20W50 conventional oil (sometimes adding some ZDDP, although Castrol 20W50 apparently has ZDDP in it). 20W50 is easily found in local auto stores.

Some say that they use 10W30 because the 20W50 may be too heavy in the winter.

Here in Virginia, it usually doesn't get too cold in the winter, and I never had trouble with my TR3 running Brad Penn 20W50 semi-synthetic, winter or summer.

So,my question: How many of you use 20W50 conventional oil year-round and find that it works fine.... in the engine and in the transmission?


Sorry to bring this up again, but it is hard to find a clear and direct answer to this question on the Internet.
 
20W50 is fine. All the two numbers mean is that when the oil is cold it has the viscosity of the lower number and when hot the viscosity of the higher number. Oil used to be only measured in the single weight. I used to run straight 50wt oil in Spridget and larger MG transmission's.

Kurt.
 
Kurt,

Many thanks. That makes it clear for me. I'll use 20W50 conventional (Castrol) oil in the engine and the transmission.

I have a lot of Brad Penn 20W50 semi-synthetic oil left over from my Triumph, but I think the synthetic nature of it is contributing to a leaking problem that I have in the Bugeye. Moreover, the Brad Penn is more expensive than the conventional Castrol. I'll stop using the Brad Penn.

Ed
 
There is another thread on this topic, but it is worth repeating the information here.

I believe (no real proof) that conventional oil (non-synthetic) is less prone to leaking than synthetic or partial-synthetic oil. A lot of racing oils are synthetic, so I am told. On the chance that all this is true, I am changing from 30W/50 partial-synthetic to 30W/50 conventional oil (so-called dinosaur oil) Moreover, I don't think the synthetic oil was generally around when these Bugeyes were built. I guess it's just a matter of faith with me at this point, because I have no sicientific evidence other than anecdotal evidenc.

But, as an added bonus, the conventional oil is cheaper than some of the synthetic oil.

What do I make of what I read that 20W/30 is gear oil? It would seem that 20W/50 would be even more appropriate as a gear oil.
I
 
One would have to take into account the context it is mentioned in. It could be that that specific 20W30 has certain additives that make it best suited for a gear case. Other than that the 20W30 definition doesn't imply that it is anything special or different.

Kurt.
 
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