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Detergent or Non-Detergent, Trans/ OD

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vette

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Hi all, Can someone tell me the reason it is recommended to run non-detergent oil in our trans and ODs. Thanks, Dave.
 
Early gearboxes have parts that might be compromised by detergents, so I use 30 wt. non-detergent. Center shift 'boxes appear to allow multi-grade detergent oils (factory handbook) as used in the engine, so I use 20w50 GTX in the BJ8. No need to worry about ZDDP here. This is what I have concluded after years of debate and questions, and it seems to be working.
Bob
 
Had this discussion a few weeks back. Best reason given is because detergent oil tends to foam more and this can reduce OD hydraulic pressure.

I'd tend to agree with the foaming thing as I run regular multigrade detergent engine oil in the 57 OD and the oil turns a light-brown opaque colour after running for a few minutes. OD works fine although the shift is quicker and sharper after sitting overnight compared to after being driven within the last few hours which I'm guessing is related to oil foaming and viscosity. The softer shift is more pleasant to drive.

Andy.
 
As Bob and Andy indicated, foaming is one reason for not using detergent oil. However, the major reason is that the Trans/OD does not have a filtration system and non-detergent oils will allow any particles or metal bits to drop out of suspension and settle to the bottom of the case (out of harms way) for elimination when draining. Detergent oils are formulated to keep these particles in suspension (to be taken out by a filtration system) and will constantly circulate and possibly cause further damage.

Ray (64BJ8P1)
 
Quantum Mechanics claims use of detergent oil will void the warranty on their rebuilt trans and overdrive units; same reasons cited above.

I'm currently using Shell 30 ND in my car, and the shifts are crisp (and instantaneous)!
 
Thanks Everyone. I decided to read the manual alittle. I do this once in a while :smile:. The manual talks about different weights and temps, etc, I was even alittle surprised that it mentions multi-weights for some conditions considering the era we are talking about. But the manual says nothing about detergent oils vice non-detergent oils. I was wondering where the recommendation came from. Your responses all make sense to me because I am experiencing same kind of situation. I'm running Valvoline 20w/50 Racing Oil in the engine. But I put 30w Valvoline in the trans and OD. I assume it is a Detergent oil. I noticed immediately upon putting it on the road this fall that the upshift into OD was not crisp at all. And twice at highway speed it dropped out of OD by itself then immediately reengaged. So I think I should switch to a non-detergent oil. Have a Merry Christmas. Dave.
 
vette said:
... And twice at highway speed it dropped out of OD by itself then immediately reengaged. So I think I should switch to a non-detergent oil. Have a Merry Christmas. Dave.
Click to expand...

Mine started doing the dropping out of OD on the highway and reengaging shortly thereafter last Spring. It was an electrical issue. I replaced both the relay and solenoid and it went away.
 
Had same problem one time--was the relay (the one on the scuttle/firewall). You can open them up--carefully--file the points and close them back up. If that fixes the problem put a new one in as the points may be very worn.
 
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