zjsheller
Observer
Here's my problem. Trans wouldn't shift up in my 96 4.0 ZJ last week and upon pulling the dipstick I discovered aerated fluid in the trans. Fluid levels are OK. Fluid looked and smelled OK (it was changed less than 10k ago).
In doing some research I have seen others with a similar problem and the culprit was a blocked trans cooler. Thinking I was going this route, I pulled the cooler and it seems fine. No blockage. I can blow through it freely.
So I then decided to check for what kind of flow I had to the cooler. I started up the ZJ and let it run in neutral with the cooler taken off. I initially got what can best be described as a big burp, then nothing. Very slow trickle. I checked the flow in drive and same result.
Now my problem is I'm not confident in translating my test results into a solution to the problem!
Is there supposed to be regular, steady flow with the trans in P or N or D?
If so, how much? It certainly doesn't seem like a cooler would be too effective with this slow of flow.
If there is some kind of blockage, is it most probably in the line?
Is there a chance thats is some sort of pump in the transmission?
Filter was changed with fluid change. Any chance thats clogged already?
What should my next step be?
Thanks in advance!!
In doing some research I have seen others with a similar problem and the culprit was a blocked trans cooler. Thinking I was going this route, I pulled the cooler and it seems fine. No blockage. I can blow through it freely.
So I then decided to check for what kind of flow I had to the cooler. I started up the ZJ and let it run in neutral with the cooler taken off. I initially got what can best be described as a big burp, then nothing. Very slow trickle. I checked the flow in drive and same result.
Now my problem is I'm not confident in translating my test results into a solution to the problem!
Is there supposed to be regular, steady flow with the trans in P or N or D?
If so, how much? It certainly doesn't seem like a cooler would be too effective with this slow of flow.
If there is some kind of blockage, is it most probably in the line?
Is there a chance thats is some sort of pump in the transmission?
Filter was changed with fluid change. Any chance thats clogged already?
What should my next step be?
Thanks in advance!!
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