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pressure readings after rebuild

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RA3Goat

Member
Joined
Apr 8, 2005
Messages
65
Just had my trans rebuilt after breaking the direct drum (http://www.turbobuick.com/forums/transmission-talk/229782-lost-od-highway.html). Seems to shift as it should at part throttle, it’s responsive and firm. I have not yet checked the full throttle shifts. It shifted great before I broke the drum. It’s a CZ trans with CK’s shift kit (which is great!) and has the basic hard part upgrades. I’ve never fried clutches in this trans (just broken hard parts!!)
Should I be concerned with the pressures below? Compared to the pressures in CK’s manual, my pressures at MinTV are higher and my pressures at MaxTV are lower. How can I fix this? Does it need to be fixed? Can this hurt anything or am I just not getting optimum clamping force on the clutches?
MinTV MaxTV
P 150 190
R 225 225
N 150 200
D4 160 215
D3 160 200
D2 200 200
D1 200 200
 
So no reason for concern?

So I guess as long as the trans shifts the way I want, it should be ok? How can I increase the pressures at MaxTV? Isn't more always better??
 
So I guess as long as the trans shifts the way I want, it should be ok? How can I increase the pressures at MaxTV? Isn't more always better??

If your line pressure gets too high it may not shift at all. Looks like something may be sticking Throttle Valve or pump pressure relief valve. Maybe someone will chime in that knows more.
 
Before it broke the pressures were:
MinTV MaxTV
P 75 200
R 115 225
N 75 200
D4 75 200
D3 75 200
D2 210 215
D1 210 215
(I think I took minTV at idle, just under 1000 rpm, that's why they are lower)

After it broke:
MinTV MaxTV
P 100 200
R 90 200
N 100 200
D4 100 200
D3 100 200
D2 210 210
D1 210 210
(minTV was taken at 1000 rpm)

So the current pressures (after being fixed) at minTV are higher.
I took it for a longer drive tonight and at part throttle it shifts firm, perhaps slightly harder then I would like, but not harsh. It will chirp the tires going into 2nd most of the time, and with a little more throttle it spun the tires a bit on the 1-2 shift. It's very responsive on downshifts too. I have not checked WOT shifts yet. It goes into OD fine too.

What would cause high minTV pressures and how do I increase maxTV (assuming I want to. better clutch holding power?)? However I have managed to break a hardened factory forward drum and now a direct drum, so maybe the clutches aren't my biggest concern. I have not dual fed the directs yet, but like I said, I'm not burning up clutches.
Thanks.
 
update: why won't my trans live?

I just took a ride to a friends house 20 miles away. took back roads the way there, mostly in drive, put it in overdrive a few times where I could do 45. a few hours later, took the highway home 55 to 65 the whole way in OD, it downshifted to pass a few people. got off the highway, put it in D and it wouldn't come out of first. pulled over, and pulled the TV cable 20 times, still wouldn't come out of 1st gear. no matter what position the gear selecter was in. what did I do? I'll check pressures tomorrow. fluid level was good and smelt fine. trans felt fine the whole ride.
 
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