Poorly made bearings

Ken/Alabama

Ken/Alabama

Well-known member
I done a rebuild on the transmission in my 40 coupe about 8 years ago and have driven it quite a bit over that time . It runs very smooth and shifts smooth and never jumps out of gear. I’m about to take a 500 mile round trip so I changed the engine oil and checked the oil level in the transmission. The oil level was fine but I noticed the oil wasn’t very clean on my finger. So I opened the drain plug and the oil looked like a can of grey metallic paint, not good ! I then proceeded to pull the transmission and an hour and half later had the transmission on the work bench. Everything looked fine untill I dumped the roller bearings and spacer out of the cluster gear. The bearings had failed because the cages were not hardened steel. The rollers had literally worn through the cage. I have no idea where those bearings came from but I know of lately there aren’t any quality replacements. I always keep good used ones and I had a coupe of NOS ones . Once everything got a good cleaning I put the new bearings and spacer in and I’m back in business. I took a file and run it across the cage on one of the old bearings and it would cut it fairly easily vs the original bearings the file would just skate across it. So check you bearings. The one bearing that is inside the front main drive was still intact but you can see that it was wearing into the cage.
 

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Ken/Alabama said:
I done a rebuild on the transmission in my 40 coupe about 8 years ago and have driven it quite a bit over that time . It runs very smooth and shifts smooth and never jumps out of gear. I’m about to take a 500 mile round trip so I changed the engine oil and checked the oil level in the transmission. The oil level was fine but I noticed the oil wasn’t very clean on my finger. So I opened the drain plug and the oil looked like a can of grey metallic paint, not good ! I then proceeded to pull the transmission and an hour and half later had the transmission on the work bench. Everything looked fine untill I dumped the roller bearings and spacer out of the cluster gear. The bearings had failed because the cages were not hardened steel. The rollers had literally worn through the cage. I have no idea where those bearings came from but I know of lately there aren’t any quality replacements. I always keep good used ones and I had a coupe of NOS ones . Once everything got a good cleaning I put the new bearings and spacer in and I’m back in business. I took a file and run it across the cage on one of the old bearings and it would cut it fairly easily vs the original bearings the file would just skate across it. So check you bearings. The one bearing that is inside the front main drive was still intact but you can see that it was wearing into the cage.
Click to expand...
575533


575534
 
This garbage pisses me off as well. I try and salvage used ones if possible. I too have noticed the new version of those bearings are crap.
 
Word has been out about these off shore bearings for some time now. What a bummer that routine maintenance turned into a trans rebuild. Glad you caught it now before they failed completely.
 
This is not a new issue. If those original roller bearings are not pitted, reuse them. This problem showed up at least 10 years ago. Another problem with the main drive gear bearing was the big snap ring was either too thick or the groove was not in the right place and the casting that holds it in didn't seat to the case well enough and oil would leak there.
 
Gosh, remember the good old days when bearings were made in the USA. I have saved a few of the used OEM bearings shown if anyone needs them.
 
The main FORD spare parts vendors are either using "KOBE" chinese brand or BALTZER who used to be made in Germany now in china as well BOWER/RBC LONG....... stopped making them as did HYATT i'd advise /suggest finding/locating&sourcing either:BOWER/HYATT/RBC or O.E.M. FORD ones.
 
Don't pass on any bearings made in Israel if they come along. They're "Mil-Spec". I believe King Bearings are made in Israel. Be careful and double check the application.
 
Another major issue with repop transmission parts are the replacement cluster cross-shafts that these bearings run on. Every replacement one I've seen is WAY out of spec and will fail in short order:

1) The material is sub-par -> with the outside hardening being nowhere close to the 60+ Rockwell of the originals. Who knows what alloy is even being used . . . but they are soft and the finish is poor.

2) The diameters are typically .001 - .002 undersize -> this causes more slop in the bearings and also increases the amount of gear oil that wants to slip past the case and onto your garage floor.

I've resorted to making my own shafts by buying high-quality linear shafting from Thompson - then machining in the "locking pin" holes and also adding O-ring grooves to the fronts/rears (to prevent gear oil leaking out).

Here are my new shafts (before I ground the O-ring grooves)

NewShafts1.jpg

Mic on my New Shafts:

DalesNewShaftDiameter copy.jpg

Mic on Original:

OriginalShaft-UnwornArea.jpg

Mic on Replacement:

NewReproduction.jpg


I don't know if Mac VanPelt has come up with any suppliers for high-quality cross-shafts, but it is worth checking in with him. Trying to find NOS original shafts is quite difficult. One trick is to turn a slightly worn shaft upside down (putting the wear on the bottom of the case). This can help in that all of the thrust is downward (up top).
 
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B&S: You are to be commended for making such an excellent replacement shaft. Well done.
I am wondering..... How do you grind the o-ring grooves?
 
Bored&Stroked said:
Another major issue with repop transmission parts are the replacement cluster cross-shafts that these bearings run on. Every replacement one I've seen is WAY out of spec and will fail in short order:

1) The material is sub-par -> with the outside hardening being nowhere close to the 60+ Rockwell of the originals. Who knows what alloy is even being used . . . but they are soft and the finish is poor.

2) The diameters are typically .001 - .002 undersize -> this causes more slop in the bearings and also increases the amount of gear oil that wants to slip past the case and onto your garage floor.

I've resorted to making my own shafts by buying high-quality linear shafting from Thompson - then machining in the "locking pin" holes and also adding O-ring grooves to the fronts/rears (to prevent gear oil leaking out).

I don't know if Mac VanPelt has come up with any suppliers for high-quality cross-shafts, but it is worth checking in with him. Trying to find NOS original shafts is quite difficult. One trick is to turn a slightly worn shaft upside down (putting the wear on the bottom of the case). This can help in that all of the thrust is downward (up top).
Click to expand...


Here are my new shafts (before I ground the O-ring grooves)
575618


Mic on my New Shafts:
575619


Mic on Original:
575621


Mic on Replacement:
575622
 
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