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Post Info TOPIC: You don't need 700hp to break a Legend Transmission


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You don't need 700hp to break a Legend Transmission
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I pulled my Legend transmission out of the car right after Christmas due to a strange whining sound in the first 4 gears. As you can see in the pictures, the inner race on one of the countershaft bearings broke into several small pieces. The inner race also has a crack all the way across it. 3 of the pieces had already fallen out of place and were stuck on a magnet glued to the midplate. It doesn't seem as though those chunks went through any of the gear teeth. All of the bearings do say they were made in China, so I ordered Timken replacement bearings in hopes that I don't have the same issue again.

What caused this???? Great question! Some would say it's my driving style, but I'm not sold on that. There was a bur on the surface that bearing sits on. Could it be it was pushed on uneven and fractured at assembly? If that's the case, I got 6,000 lucky miles out of it.

Where do you get parts for this you ask? Another great question. For the bearings, I cross-referenced from the numbers on the old bearings. My next dilemma is shimming the tapered bearings properly. From the research I've done, a general rule of thumb is to have .002-.004" preload on these tapered bearings. After installing the new bearings, I assembled the shafts in the case and measured end play. As I feared, the new bearings have a slightly different installed height than the originals. I have been to 3 transmission shops to find the proper diameter shims to finish my project. I found a place that let me shop the shim shelf in the shop. I have found some that are close, and I will have to grind on them a bit for proper outside diameter. 

I knew if I had an issue with this transmission, parts acquisition was going to be tough. If these shims will fit, I believe I can move on to clean up and final assembly. An incredible ice fishing season has really slowed down progress as of late, but there is plenty of time . . . right?? 

 



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Chris S.

Oak Grove

'68 Malibu (His)

'68 442 (Hers)



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I would bet the inner race was was cracked at install. That doesn't look like an abuse fracture, although your "driving style" would certainly qualify for that...laughing

Good catch on the slight wine symptom and investigation before it came apart completely.



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Mitch D.   River Falls, WI

Charter member of the "Cars apart Club"

Some Assembly Required

1966 Chevelle SS 396 M20

1970 Chevelle SS 396 M20



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Sorry it is giving you problems.

 

Imgonnadohconfused

 

Karl



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Great job on being proactive, and not just forgetting about it, seems you have a good ear .

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Bruce L. - Lakeville MN

1971 Malibu Convert

1951 Pontiac Chieftain Super Deluxe Catalina Hardtop 



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John D. - St. Louis Park, MN.

1965 El Camino - LT-1, 4L60e, 4wh discs, SC&C susp.
2013 F-150 Platinum - Twin Turbo 3.5

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Chris S wrote:

You don't need 700hp to break a Legend Transmission


 

butithelps.jpg



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Derek Kiefer - Mantorville, MN

69 Malibu Pro-Touring stroker LS1-383/T56 - 69 SS396-325/3spd project



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Got out for a shake down run tonight and the tranny works well. I don’t remember it ever shifting this nice. Can’t wait to put more miles on!!



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Chris S.

Oak Grove

'68 Malibu (His)

'68 442 (Hers)



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Now that is great news. Nice repair work. The Chris brothers did it again!

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'69 Convertible,  Lemans Blue, 454, 200 4R, 12 Bolt. 

Jon H.  Lino Lakes

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