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700r4 Transmission whine

24K views 11 replies 5 participants last post by  oldchevy1956 
#1 ·
I recently installed a higher stall converter in my 56 chevy with a 383 and 700r4. I did not change anything else but the converter. I went from a stock locking converter to a higher stall 2400 locking converter. Now when I put in gear and only in gear as I accelerate there is now a whine type noise. It is perfectly quite in park and neutral at any rpm. The whine is at the same speed as the engine and seems to be present no matter what gear the trans is in. The trans shifts and downshifts correctly but I don't like the whine and don't think the whine is good. Fluid level is correct and all bolted back up perfectly. I am sure this is related to the converter since this is the only thing I changed but why? Any help would be appreciated.
 
#2 ·
Since this happened with the converter change, only in gear, not in neutral or park,

I would suspect a torrington bearing in the converter may be making noise.

Do you have a dust cover on the trans? If there is excessive crank shaft end play , the flywheel may rub the dust cover or the cover was slightly shifted off to one side.... Just a thought, I've seen it
 
#3 ·
After listening to the whine some more I also should add that I did a filter and pan fluid change as well. So after changing the filter and converter I have done a complete fluid change. I add this as could there be an issue with the filter or pump sucking in air some how? It sort of sounds like a power steering pump when low on fluid. I also have taken off the converter cover but no change in the whine. Fluid level in trans is full. I even added some additional fluid to verify was not low but no change. Now I am over filled but just about to take the pan off anyway to check the filter and such.
 
#6 ·
When you had the transmission out on the floor, did you fully seat the torque converter on the trans shaft and measure to the face of the transmission flange? Torque converters sometimes need shims under mounting bolts to shim out the converter so it fully engages into the trans. This can cause a whine but I think it would not be dependant on gear engagement. You would hear it whenever the engine is running.

Jim
 
#7 ·
I did not leave the filter seal or o-ring in the trans but I plan to check the filter very closely tomorrow when I remove the pan and do a close inspection. I did measure the torque converter mounting and such with fitment on the flywheel and all seemed normal. I have replaced dozens of converters on fords and chevys and never had this happen. I will post once I take the pan off and inspect the filter.
 
#8 ·
I took the pan off and changed the filter but honestly all looked fine with the old filter. Same whine as before. Only whines in drive and reverse. All forward gears still whine and whine is with engine speed not trans gear or car speed. Any additional ideas? Probably going to swap out the torque converter with a new one.
 
#9 ·
oldchevy1956 said:
I took the pan off and changed the filter but honestly all looked fine with the old filter. Same whine as before. Only whines in drive and reverse. All forward gears still whine and whine is with engine speed not trans gear or car speed. Any additional ideas? Probably going to swap out the torque converter with a new one.
like crosley mentioned in his first reply to your post, its going to be in the converter you installed.
if it was a filter or pump problem then, it would make noise in all ranges. not just while in gear.
 
#10 ·
I have purchased a new converter (from Jegs) and will install as soon as I get it. I have noticed though that the converter I just took out (purchased from a local shop) was supposed to be new but it is fairly clear to me that it has been rebuilt. Not that a rebuilt unit would be bad, but I was expecting a new one the first time. I will replay once I get the new converter installed.
 
#11 ·
oldchevy1956 said:
I have purchased a new converter (from Jegs) and will install as soon as I get it. I have noticed though that the converter I just took out (purchased from a local shop) was supposed to be new but it is fairly clear to me that it has been rebuilt. Not that a rebuilt unit would be bad, but I was expecting a new one the first time. I will replay once I get the new converter installed.
the converter from Jegs is not new, as in all new parts. The converter will be a rebuild / remanufactured unit also.

Converter companies reuse converter parts and install new bearings, roller clutch, thrust washers and machine various parts to achieve the desired results
 
#12 ·
I swapped out the converter with a Hughes 2500 stall locking converter that I purchased from Jegs and the whine is gone. So the problem was obviously in the convert as I was told. Thanks for all the advise. The transmission shifts perfectly and I definitely enjoy the higher stall converter.
 
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