Shorter CV / birfield & thick drive flange.. doh (1 Viewer)

[itchy355]

Hi all

So yesterday we were replacing everything on a friend's 1995 front end. Deal was he gets the parts, we do the work (I get a transmission replace work in exchange, looking forward to that!)

He got new birfs, seal kit, all good, let's go.

After everything was back in, the spline won't reach far enough to put the c-clip back on. What the..? And then itchy355 remembers. There were two different lengths of birfs and two different flanges to pair that. Apparently the supplier not knowing the eighty's just ordered a CV joint and we're stuck in a situation of a short birf (short splined) and a thick flange.

Of course the correct solution is to take everything out and have the dealer replace the correct birfs. Yup.

Solution #1 that came to mind, machine some 8 millimeters off the drive flange and be done with it.

Solution #2 that came to mind; how about we use the 8mm threaded hole (meant for pull-out screw) and fix a wide & strong washer to act instead of the c-clip? Drawing attached. I mean; there's no rotation whatsoever at that spot apart from a very small play in the splines. If some loctite is applied and the screw would be tightened enough, I don't see a way of this unscrewing during any use. The only thing I'm worried about is the screw would get torn off; but really, is there enough lateral force for this to happen?

Then replace in a year or two, after money won't be the issue any more. Keep the short birfs for emergency.

 

[Woofythewolf]

Just out of view to the left of your section view is the reason #2 won't work, there is a flange bushing that runs against the shoulder of the CV joint to be the wear surface preventing the CV from coming outwards. Why toyota didn't put another snap ring or something on the inside of the drive flange idk, but instead it's got another wear surface there.

Tighten a bolt there and it's not going to spin anymore. (until you give it some gas, which will force it, and then you get bronze particles all throughout your knuckle and $120 in bushings trashed)

I'd just get the shorter drive flanges (from the earlier year trucks IIRC), or take it to the lathe but be very exact on the dust cap press fit. You don't want to struggle next time if it's too tight.

 

[ppc]

Personally I would return the short birfield. Using the narrow drive flange gives less engagement in the splines making them easier to strip the drive flanges, the reason for the change was made during production.

Rather than putting a bolt and washer on the end checkout the "Martac" modification to the axle.

 

[mudgudgeon]

Option 1, create second **** up to hide the first.
Option 2, create a different **** up to hide the first.

Whichever option you choose, you have 2 **** ups to fix at some point.

The shorter spline engagement is prone to excessive, rapid wear.
This is the reason the birfs and flanges were changed.

While you're in there, pull the birfs back out and change them for the correct ones. Everything is clean, now is the time to bite the bullet and do it

 

[itchy355]

Oh it's not like the washer would be tightened against the flange, but against the birf shaft; there still would be small (<2mm) lateral play as it's when secured by the c-clip. The birfield body should not be tightly pressed against the spindle. If so, the washer would need to be machined with that in mind. I don't have an exact photo of the situation but it looks somehow like this here (it's a hundred but the situation is similar)

https://forum.ih8mud.com/attachments/img_20210906_102233-jpg.2778608/

It's protruding out through the flange alright, but not nearly enough.

My painting skills suck)

 

[itchy355]

.. and here we go

Snap ring? Or not?

This is the internet at work here. Put all three in your hand and make decisions. Put all three on your screen and make assumptions. I don't have all three. can you throw a tape on them and show the difference? I am interested, makes sence about the gear not engaging all the way...

forum.ih8mud.com

apparently there have been people using it.

Again I know it's not a correct solution. If it were my truck I would buy the correct birfs as well. Not my truck, just want to be helpful here as the owner is already well beyond his planned budget )

 

[mudgudgeon]

If it's up on a lift or on stands, you've got maybe 1 -1 ½ hour each side to swap out the birfs.

The slowest part of swapping birfs is cleaning all the dirty parts on tear down. If everything is clean, it doesn't take long to zip out some bolts, pull stuff apart, swap birfs and button it all back up again.

 

[itchy355]

Oh the truck is in pieces. Cab here, frame & engine there, axles elsewhere )

The only problem is the owner is really getting frustrated over this money subject. He's bought it for like USD 14000 and he's in another 10k in parts & work already. I'll see how it turns out

 

[CrabCake]

If there is no rush, get the right parts and do it correctly. It's not like you are doing a field repair to get off of the mountain...

 

[mudgudgeon]

^^^ particularly if the supplier sent the wrong parts

 

[LandLocked93]

The only problem is the owner is really getting frustrated over this money subject. He's bought it for like USD 14000 and he's in another 10k in parts & work already. I'll see how it turns out

Well he's paid the right amount to only cry once.

 

[landtank]

I have a pair of brand new OEM short drive flanges and could have them to you for Monday

 

[landtank]

Here they ate

 

[mudgudgeon]

Well he's paid the right amount to only cry once.

Will he only cry once though?

 

[itchy355]

@landtank pm sent

I think he's already cried many times and it's not over yet. Nobody's touching the engine for example; yeah it's a tough one to destroy but heck. I'll have some pictures later maybe; I'm really proud of my mechanic for his work on the frame; everything is either zinc coated or new, looks absolutely great. Sadly there's no money left for the same work on the axles so they're staying rusty.