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zf 4hp22 what is max oil pressure that would be seen in gearbox oil cooler

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I am looking at aftermarket gearbox oil coolers and I know the oil pressure measured on a gauge plumbed in to the connection on the front of the auto box should show 100psi at idle and 150psi at 200rpm according to the service manual (both +- 5psi)

I have two questions

1. is this the pressure that would be found in the oil cooler and its plumbing?

2. would the pressure go higher at a higher rpm?

looking at the motamec cooler it is rated at 145psi and the mocal at 150psi so both are borderline for the service manual pressure

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1. No. It is a return line, after it has done the work in the box. Likely 30psi, max.

2. Shouldn't do, there is no restriction as it heads back into the pan, so no way to build pressure.

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I’ve heard it was under pressure and the flow reversed and all sorts. But, I ran ordinary rubber hose onto non-swaged pipe and didn’t have an issue. Normally these things are low pressure. Also, I doubt you can buy an oil cooler with such a low pressure it could pop it? 


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