U-joint cap not tight

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Feb 4, 2016
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Broomfield, Colorado
Finally getting around to replacing bad front u-joint. When trying to remove c clips from bad one, it was odd that the cap was spinning in the yolk which made removing the clips a little challenging. Upon installing new u-joint I could basically press the caps in by hand. Little tighter than the old one, but definitely not tight. I'm assuming this is not normal and probably not safe? The new u-joint is the proper part number ordered from cruiser outfitters. Any input appreciated.
 
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My experience is that Neapco U-joints fit loosely in the yoke compared to OEM. You should need to press them in. Any slop of play is bad.
 
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Lake Waconia, MN
I recently replaced all 4 of my u-joints. 4 of the 16 caps were like yours and spun.

All that is needed is to peen the inside diameter of the yolk where the cap "presses" into. I use a simple and cheap automatic center punch and put approx 8-10 small peens per yolk around the bore. The caps press in nice and tight. Install the u-joint and caps normally, no other special tricks are needed. This just tightens up the bore on the cheap so the caps don't rotate.

I've replaced hundreds of u-joints when I was an auto tech. This is a common practice in automotive repair when the caps are loose - The caps must not rotate!

Do not do this of the bore of the yolk is damaged, out of round, cracked or bad in any other strange way - the yolk / shaft must be replaced at that point.

Amazon product
Peen this area with the automatic center punch 5-10 times around the diameter - problems solved.
Peen.JPG
 
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Joined
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The brand of u-joint really doenst matter. From my experience, it has more to do with the shaft / yolk wear and tolerance than the u-joint caps themselves. I've seen loose caps on every make of vehicle using every make of u-joint, factory parts to cheap aftermarket parts. YMMV.
 
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All that is needed is to peen the inside diameter of the yolk where the cap "presses" into. I use a simple and cheap automatic center punch and put approx 8-10 small peens per yolk around the bore. The caps press in nice and tight.
Just my 2 cents, but being a UAW Journey man machinist/mechanic for over 30 years putting those prick marks inside the yoke did NOT correct the underlying problem. Under load those 8 to 10 prick marks will not keep that cap from moving, those caps NEED TO BE PRESSED IN so the U joint turns on it's needle bearings, not the caps turning inside the yoke bores. The correct way to fix this problem is to buy the correct sized U joints that press into the yoke. YMMV
 
Joined
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Messages
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Just my 2 cents, but being a UAW Journey man machinist/mechanic for over 30 years putting those prick marks inside the yoke did NOT correct the underlying problem. Under load those 8 to 10 prick marks will not keep that cap from moving, those caps NEED TO BE PRESSED IN so the U joint turns on it's needle bearings, not the caps turning inside the yoke bores. The correct way to fix this problem is to buy the correct sized U joints that press into the yoke. YMMV
I like this as well.
 
Joined
Feb 4, 2016
Messages
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Location
Broomfield, Colorado
So what would be my best option? I ordered the correct replacement u-joint and the original was spinning so I'm guessing the yoke is just worn. Buy new yoke? New driveshaft? Try the preening and lock tight maybe?
 
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Feb 4, 2015
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B Todd, I've use Loctite 620 retaning compound with good success on worn bores, but I'll warn you if you have to remove that U joint sometime down the road, you"ll first need to heat it with a torch to break the Loctite bond, otherwise you'll have a he11 of a time trying to remove it. If the yoke bores are worn more then .008 (that's the limit of Loctite 620) you can use Loctite 680, it'll work with worn bores up to .015 of an inch. But if your yoke is worn that bad, it really would be best to buy a new one.
 
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X2 on the locktite.

I didn’t know that the UAW represents mechanics. I was IAM (aka IAMAW) while I was turning wrenches. Now the UAW represents graduate students and teaching assistants at the university who don’t know which end of a wrench goes where.
 
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I know some mechanical engineering professors that don’t know which hole the oil goes in for their car, but yet they do know how to build some cool machines.
 

Irish Reiver

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For what it's worth, last year i priced new OEM U- Joints and a rebalance at my my local driveline store. Price wasn't too far below the cost of new driveshaft from toyota. So that's what I did. No more U-joint play, no more yoke play and it's already balenced.
 
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