lost OD on highway

RA3Goat

Member
I was cruising around 80 at 3 grand, started feeling like the engine was revving slightly higher (few hundred rpm's) than usual at that speed and feeling like the trans was starting to fight back. I've had transmissions die on me a few times, so I know when things aren't going right. Suddenly it felt like the trans slipped briefly, then came out of OD and went into 3rd. This is a non-LU trans. I got off the highway and took back roads home for 10 miles, no problems. I pulled over and checked the fluid, it looked and smelt fine. Pulled on the TV cable several times, to possibly clear any junk that might be in the valve, but no change. I happen to have a pressure gauge hooked up and there was no change or fluctuation in the pressure when all this happened.
So now, with the gear selector in D it won't shift past 2nd, and with the gear selector in OD it won't get past 3rd. I have not driven the car since parking it after this. I was just glad to make it home.
Any ideas on what to check or what would cause this?

One more note: I ran the car on a chassis dyno for the first time just before this. See attached. I've got some tuning to do.
 

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did you check the shift cable? maybe came loose? is neutral still the same? just some things to check if you haven't already...try using the column to shift to shift it .....make sure you can get all gears
 
Thanks for the reply. The shift linkage is on my list of things to check. But would that cause it to come out of OD? The rest of the gear positions seemed fine, PRN21. Would shift through 1, 2, and 3, just wouldn't go into 4th. i haven't really brought to motor past 5 grand, so I'm not sure if 6000 rpm's in 3rd hurt the trans. I don't see why it would, it wasn't shifting.
 
now no reverse

I checked the shifter linkage and positions. Everything was good, hasn't changed. Still no overdrive and now I noticed reverse is gone, low pressure, just slips.
Any ideas? I guess I'll drop the pan and take a look.
What may cause this? Broken hard parts? Gasket leak?
Still chirps the tires on the 1-2 shift.
Thanks.
 
Odd things

I had a 155 thermostat and running on the highway, it ran cool enough to disengage the TCC. Also had a brake pedal hang up.
Just some thoughts.
 
update: loose filter?

Finally had time to pull the pan. Fluid looks great. Normal amount of residue stuck to magnet. No metal pieces.
The only thing I noticed was that the filter was not fully inserted; it hung by itself, but was touching the bottom of the pan.
Would this cause low pressure only in reverse? But still allow the forward gears to shift ok? But not shift into OD?
I'm going to put some type of spacer (that won't move) between the filter and pan and see if it goes back to normal.
Any one know how much space there is between the bottom of the filter and the pan?
Thanks.
 
That spacing is easy enough to figure out now that the pan's off. Insert the filter to it's proper location
(make sure there isn't an extra O-ring up in there which s a common problem when filter changes are done. Old filter gets pulled out, leaving an o-ring behind, new filter gets inserted and old o-ring wont allow it to be fully inserted).
Measure from the tranny pan rail down to the lowest point of the filter. Now measure the depth of the pan from it's rail.
The difference is the clearance.
 
trans problem

May be your TCC solenoid. If your trans is a non lock up then you will have no fourth gear. Fourth gear in a 200r4 is overdrive gear. Converter has to lock up to go into fourth.
 
May be your TCC solenoid. If your trans is a non lock up then you will have no fourth gear. Fourth gear in a 200r4 is overdrive gear. Converter has to lock up to go into fourth.

Huuhhh???? :confused:

Who told you that????

You got some bumm dope somewhere?
 
May be your TCC solenoid. If your trans is a non lock up then you will have no fourth gear. Fourth gear in a 200r4 is overdrive gear. Converter has to lock up to go into fourth.
NOT TRUE!!!! I have had a non lock up 9" converter and drove to BG for years with it in (OD) and it was just fine!

+2 what dave said.... :D

Scot W.
 
Sounds like the OD roller clutch failed or is failing since you state the line pressure is good. Time to pull it.
 
stronger parts?

Thanks for the replies. I put in a new filter and put it back together. The car moves in reverse but not the way it should, and the fluid doesn't show any signs of clutch slippage. I haven't checked to see if it will go into od. Pressures at min TV looked ok.
If it turns out to be the OD roller clutch, is that common? What is the main cause of failure? Was it something I did? Are the reverse clutches slipping since it moves slowly? The 3-4 shift was firm but not harsh. Is there a stronger one that can be installed? Any billet parts that would help? Not that I want to spend any more money on this trans!
I have the CK billet forward drum (broke a hardened one before), and shift kit/spacer plate. I'll probably dual feed the directs while it's out too.
Thanks again.
 
I would check/replace the front pump. It went out on me and I couldn't get into overdrive. New pump=overdrive

He said line was good. Pump pressure circuit is out of the picture. The trans isnt transferring power through it. That is unless the stator tube came loose and walked rearward taking out the front of the trans as well as the converter. I saw this happen on one. Not a good thing at all. It needs to come out.
 
Thanks for the replies. I put in a new filter and put it back together. The car moves in reverse but not the way it should, and the fluid doesn't show any signs of clutch slippage. I haven't checked to see if it will go into od. Pressures at min TV looked ok.
If it turns out to be the OD roller clutch, is that common? What is the main cause of failure? Was it something I did? Are the reverse clutches slipping since it moves slowly? The 3-4 shift was firm but not harsh. Is there a stronger one that can be installed? Any billet parts that would help? Not that I want to spend any more money on this trans!
I have the CK billet forward drum (broke a hardened one before), and shift kit/spacer plate. I'll probably dual feed the directs while it's out too.
Thanks again.
If you have line in reverse you are not going to slip. It will be a higher pressure than the other gears at full TV. If you were slipping it would fry the oil and clutches quickly.
 
Thanks Bison.
I figured the cluthes weren't slipping since the fluid still looks/smells new.
I took a ride to confirm it will not shift into 4th when the gear selecter is in OD and will not shift past 2nd when in D. Pulls fine in the forward gears. Also the line pressures at min TV are about 100psi; 210psi for D1 and D2. At Max TV only 200psi; again 210 for D1 and D2. CK's book says they should be higher.
I'll let you know what I find when I pull it apart.
 
I know you've probably checked, but have you tripple checked your linkage/cable hookup?

For instance. Disconnect the cable down on the tranny lever. Put the shift lever into OD. Now, move the tranny lever to park and bring it down into OD.

Does the disconnected cable connector align with the hole it was removed from? If not, make it so.
 
The shift linkage still lines up in all positions.
The line pressure in reverse was 90 at minTV and about 200 at max TV.
 
finally got tranny apart - broke direct drum

I finally got the tranny apart. Turns out I broke the splines inside the direct drum (picture attached). What would cause this? How can I prevent it from happening again?
 

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  • 200R4 direct drum broken.JPG
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