#1  
Old 12-02-2011, 02:09 PM
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BB1968 BB1968 is offline
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Im no tranny expert by no means, but i would try changeing the filter first...It is possible that the filter is clogged just enough to make it slip until it gets the fluid warm and up to pressure...

  #2  
Old 12-03-2011, 12:04 PM
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PunchT37 PunchT37 is offline
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I would start out like stated above. Maybe just a blocked filter. Pull the pan and do a filter change. Look for crap in the bottom. That might tell you something.

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Old 12-03-2011, 04:15 PM
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Does it do the same thing in reverse when it's cold? If its a fluid problem, it should slip in reverse as well. It could be a sticking valvebody spool valve. Check the fluid, filter and valvebody. Also check for restricted cooler circuit.

What I really suspect is that the tranny is high mileage and the seals have gotten hard in it. This allows fluid to blow by the apply piston and the clutch wont apply until the fluid warms up. Since the complaint is slipping in 1st I suspect the fwd clutch pack.

The forward clutch is the only clutch used for 1st gear. If the tranny is slipping in 1st, that's the fwd clutch that's slipping. It's also used with the intermediate clutch for 2nd gear and the Direct clutch for Drive. If the FWD clutch is slipping, eventually it will fail and you'll lose all forward gears, but reverse will still work. Reverse uses low/reverse clutch and direct clutch.

If you heard any squealing, squalling in 1st or reverse, or found broken sprag parts in the pan, I would suspect a low sprag failure. The low/reverse sprag (different from the low/reverse clutch) is a spring loaded gizmo with rollers used only in low and reverse, to hold the rear planets stationary. But it doesn't affect 2nd or 3rd unless it totally comes apart. If it was the reason, it would slip in 1st and reverse, but the tranny would make noise and put metal in the pan.

The best thing to do is to let the fluid warm up before you try to drive it. If it tries to slip in 2nd or Drive, park the car because the tranny is on the verge of failing the clutch plates and stranding you.

Unless you find something simple, a slipping tranny indicates impending failure.

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Last edited by chiphead; 12-03-2011 at 04:27 PM.
  #4  
Old 12-03-2011, 06:05 PM
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Ben M. Ben M. is offline
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Quote:
Originally Posted by chiphead View Post
Unless you find something simple, a slipping tranny indicates impending failure.
This has been my experience with most transmissions too. If it slips, it's going to fail in the future and get worse.

  #5  
Old 12-09-2011, 03:53 PM
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72LuxuryLeMansLa. 72LuxuryLeMansLa. is offline
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Quote:
Originally Posted by chiphead View Post
Does it do the same thing in reverse when it's cold? If its a fluid problem, it should slip in reverse as well. It could be a sticking valvebody spool valve. Check the fluid, filter and valvebody. Also check for restricted cooler circuit.

What I really suspect is that the tranny is high mileage and the seals have gotten hard in it. This allows fluid to blow by the apply piston and the clutch wont apply until the fluid warms up. Since the complaint is slipping in 1st I suspect the fwd clutch pack.

The forward clutch is the only clutch used for 1st gear. If the tranny is slipping in 1st, that's the fwd clutch that's slipping. It's also used with the intermediate clutch for 2nd gear and the Direct clutch for Drive. If the FWD clutch is slipping, eventually it will fail and you'll lose all forward gears, but reverse will still work. Reverse uses low/reverse clutch and direct clutch.

If you heard any squealing, squalling in 1st or reverse, or found broken sprag parts in the pan, I would suspect a low sprag failure. The low/reverse sprag (different from the low/reverse clutch) is a spring loaded gizmo with rollers used only in low and reverse, to hold the rear planets stationary. But it doesn't affect 2nd or 3rd unless it totally comes apart. If it was the reason, it would slip in 1st and reverse, but the tranny would make noise and put metal in the pan.

The best thing to do is to let the fluid warm up before you try to drive it. If it tries to slip in 2nd or Drive, park the car because the tranny is on the verge of failing the clutch plates and stranding you.

Unless you find something simple, a slipping tranny indicates impending failure.
I think it would be what I highlighted in red above. So far there is no noise and only occurs when it is really cold and only when taking off from a dead stop. I have since made sure to warm the engine up thoroughly and shift through the gears a few times with the brake depressed before leaving the house. I depress the gas slowly and if it slips I stop and try again in a few minutes and have had little trouble since.

Thanks,
Karl


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