Hey all, Just finished a stock rebuild on a 700r4. Reverse and manual 1 work great, but nothing else does. In OD,D and 2 in idle car will creep VERY slowly forward. Give it gas and it free wheels like neutral. I'm going to check the governor, but seems like first gear should work in OD, D, and 2 if it was the governor. According to the attached diagnostic chart, all hard parts used in OD, D and 2 are used in manual 1 which works, so the hard parts should be good? Right now I'm thinking a valve body problem. Anybody offer any input (besides put in a th350). Dutch
Yeppers I ran into something similar on a TH350 build I did a couple years back. Ended up forgetting to put one of the outer large o-rings on one of the drums. Also make sure you put them on in the right direction and that you chased it around since it is a lip type seal. As for being a valvebody or Governor problem... that is unlikely. How was the pan when you took it off.... did the left over fluid in the bottom look like a heavy metal flake paint?
The same parts are applied but in manual 1st and rev the low and rev clutch is also applied.. I expect you need to take it back apart and look in the input hsg again . Like other poster said probably have a cut or missing seal in the forward clutch
Guys, thanks for the input. Old fluid was ok. Trans was good when I tore down, but the center support sprag was noisy. Sounded like an air raid siren. I'll pull the input drum and double check everything.
Let us know what you find. We nicked a few trying to the the forward drum back in a 700R4 just a week ago. It ****s cause you dont find out till its back in the car.
I went through something similar with my 700R4 rebuild. Pull the kick down cable at the carb forward untill you feel spring tension then let it snap back. Do it a few times - it fixed mine. For some reason they seem to get trash stuck. Hope this is what it is!
^^What he said-do this when the engine is idling in park-microscopic **** gets around the base of the plunger on the TV. has worked for me also...Worth a shot before taking it all apart again.
Your problem is with the low/reverse one-way clutch (sprag). It is not holding the rear planet. When you go to manual low, the low/reverse clutches are holding the rear planet. Hope this helps you a little more. The problem should be in that area.
I would have to agree with 63feuni. If you nicked a seal in the forware clutch it would slip in manual 1 also/
Forward sprag is installed backwards. If you drive it in manual 1st, wind it up to about 20 mph, then shift into manual 2nd, etc. If all your gears are there, then it is def. a sprag issue.
Appreciate the input guys. It's up on the bench, will check forward sprag, fwd piston, and l/r sprag tonight. Looking at the chart, MalibuKasey makes sense. In Man1 the L/R piston & the fwd piston are applied. ***uming the fwd piston is not applying sue to a bad seal, motion is transferred through the L/R clutch. In OD,D, and man 2, the L/R piston is not applied and the fwd piston is not applied because of a bad seal so there is no motion. Does that sound logical? I'll let you know what I find. Dutch
gtkane - There is no 2nd manual on the upshift, just like neutral. 63feuni- My l/r sprag (631 on the attached) turned both ways, but you are calling it a one-way? If it should only turn one way which direction should it turn if you hold it facing "forward". The forward sprag only turned one direction. It turned clockwise if you are holding the small end (574) looking at the big end. Can you confirm that is correct? Thanks guys, Dutch
You have found your problem. The l/r sprag should turn in a clockwise direction only, looking at it from the front of trans. Your input sprag (forward) is correct. The 700 trans is easy to work on just keep it super clean. You can also air check all your clutch packs and band for proper apply, check your manual. I'm sure you can get it fixed. Hope this helps you.
just to confirm, the inner "race" (664 on the diagram) should only turn clockwise, or just the spring and roller cage (654)?
The inner race (664) is the one that should turn. The spring and roller cage should stay stationary. Check your center support (630) for signs of wear. Also, make sure your spring and roller sprag is for a 700. The TH350 has an almost identical looking sprag except it is shorter. The inner race should be completely smooth, make sure you have no pits or nicks on the race surface. Its good practice to always replace both sprags, save you a lot of problems later. Stay away from the china **** if possible. Nowadays all you get is hecho in china ****.
Bingo, the l/r sprag is spinning both ways. The fwd piston and the front sprag are good, but the 3/4 piston seal was nicked. Parts are on their way. I'll let you know the verdict once it's back in the car. Thanks for your help guys. Dutch
If the low roller was not functioning, it should have been able to manually upshift to second like gtkane said.
Success! after replacing the l/r sprag we are rolling, 4 forward and 1 back. Thanks to all especially 63feuni ! Dutch
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