rear axle yoke--replace?

[Megunticook]

As I mentioned in the thread about replacing my bed, I'm taking advantage of how accessible various things are with the old bed off--including my rear drivetrain. I've removed and reconditioned the shaft and am wondering about replacing the yoke. It's pretty rusty and there's even a hole in it as you can see here:
http://edgeis.com/graphics/projects/truck/drivetrain/rear-axle-yoke.jpg
Has anybody here done this? I read the FSM about it, sounds like basically you just need a tool to hold the yoke from turning while you loosen the pinion shaft nut that holds it on (torqued to 300 ft./lbs.!). Is that all there is to it?

How about the installation? Any pitfalls to watch for?

I'd really rather not get into this if I don't have to (the current yoke was installed by a shop in '97 when the pinion gear was replaced), but then again I have the drivetrain out and things will never be this accessible again once the new bed's on there.

Thanks.

[bherder]

I've pulled the yoke before....

I used a 36" pipe wrench on the yoke, to keep it from turning (Spun it around till the end of the wrench was planted solid on the floor..)

I forget exactly what size the nut was, something like 1 1/8" - 1 3/16" - 1 1/4" ... Something like that .... I have the socket in my tool box somewhere.... ;) .... But I know it took a 3/4" breaker bar WITH a 'cheater bar' on the end of it to break it loose...

Maybe I'm not looking at the right part of the pic, but I don't see any hole.. ??

I'd just have the yoke cleaned off, any hole filled in with welding rod, paint, new seal, and put it back together... Oh, and run a tap through the threads that the U-Joint strap bolts go into....

[DiverDwnPowrRam]

look for the hole behind the yoke....DAMN...i have been on battlefields where the metal was in better shape then your 30 year old parts...those salt roads really eat you guys up....amazing

[Megunticook]

I used a 36" pipe wrench on the yoke, to keep it from turning (Spun it around till the end of the wrench was planted solid on the floor..)
Sounds like a good method. Once the nut is off, can you just slide the yoke off the shaft by hand?

And on the install, how did you torque the nut accurately? From what I understand that's critical.

Maybe I'm not looking at the right part of the pic, but I don't see any hole.. ??
It's along the top of the seam where the tubular portion of the yoke meets the wider circular "flange" (or whatever you call it). It's probably not a serious structural issue, since that portion of the yoke doesn't have any force applied to it, but it's just a matter of time before I lose material in areas where it does matter.[/QUOTE]

I'd just have the yoke cleaned off, any hole filled in with welding rod, paint, new seal, and put it back together... Oh, and run a tap through the threads that the U-Joint strap bolts go into....
Yeah, could re-use the old one. Although I don't weld, so I'd have to pay somebody to do that. May be worth just getting a new one, will have to price it out. Where do you like to go online for drivetrain parts?

[Megunticook]

DAMN...i have been on battlefields where the metal was in better shape then your 30 year old parts...those salt roads really eat you guys up....amazing

30 years? Try 11...I looked through my old receipts and a transmission shop replaced that yoke in '97.

I actually believe that most of the serious corrosion here has happened in the last 6-7 years, since the road crews started using that new liquid salt. They like it because it melts the ice and snow better than the traditional granular stuff they used for decades...but it comes at a high cost because it eats metal alive. Talk to any mechanic around here (not just around here but a lot of places where the stuff is used) and they'll tell you that since the mphliquid salt arrived they've been replacing brake lines like crazy, and 2 years later the new steel line they installed is rusted through (nickel-copper alloy brakelines are becoming pretty popular now--I replaced all mine with that stuff a couple years ago).

Truckers hate the stuff. Been a lot of controversy because while it makes the roads "safer" (although why people feel they need to drive at full speed during winter storms is beyond me), there's a huge hidden financial cost to everyone. The Maine DOT spokesperson just denies it's a problem when confronted by the press or public, but it clearly is.

That's why I'm anxious to get my frame painted up before it's gone!

[bherder]

Sounds like a good method. Once the nut is off, can you just slide the yoke off the shaft by hand?

Yeah, it should just pull straight out.. (correction on the socket size.. checked the toolbox ... 1 5/16")

And on the install, how did you torque the nut accurately? From what I understand that's critical.

I didn't torque it... Just tightened it up till it wouldn't tighten up any more.. :D Still together after a couple years...

[B-300]

The past that is rusted thru is a slinger on the yoke. It protects the seal underneath from debris. I would worry more about the driveshaft.
If the last 3# on near the bottom edge are 489 it's probably a 29 spline yoke. (used on 68-73 model years)
The 742 uses a 10 spline yoke. The weakest 741 also uses a 10 spline yoke.
The 29 spline is harder to find and costs more usually... I have one on my van.
The nut should be torqued 180-200ft-lbs according to the book.

[Megunticook]

The past that is rusted thru is a slinger on the yoke. It protects the seal underneath from debris.
Interesting--it certainly doesn't look like it would be a critical part of the yoke, but of course I don't want it to corrode any further. And I should have close look at the cylindrical part of the yoke "tube."
I would worry more about the driveshaft.
I pulled it, wirebrushed all the loose rust off, primered it and then 3 topcoats. There was some pitting on the shaft tube but no visible cracks, pinholes, or dents, so while I suppose it may be slightly weakened I'm going to keep it in service. Yokes looked like new (the shaft was replaced in '97).
If the last 3# on near the bottom edge are 489 it's probably a 29 spline yoke. (used on 68-73 model years). The 742 uses a 10 spline yoke. The weakest 741 also uses a 10 spline yoke. The nut should be torqued 180-200ft-lbs according to the book.Thanks--I'll see if I can find that number. According to the receipt from the tranny shop from '97, it's a 10-spline pinion shaft. I found a 1360 series 10-spline yoke online at a drivetrain specialty shop for $110, so at least I have a sense of what a replacement would cost.

[B-300]

Those receipts can can be handy for replacement knowledge down the road.
I mentioned the drive shaft as I twisted up a rusty one on a cold morning with a fast idling engine..... It was in worse shape.
I would call that liquid salt "liquid rust". It must be hell on bridges and vehicles that are unibody type construction.

[Megunticook]

I would call that liquid salt "liquid rust". It must be hell on bridges and vehicles that are unibody type construction.

Last year one of the papers here did a big story on it, they talked with a lot of different people and did a fair amount of research. The thing that the DOT boys don't seem to want to take into account is just how much extra expense this stuff is creating for everybody--including them (or us taxpayers, since that's where there money comes from). I imagine their maintenance budget, both for vehicles and things like bridges, is way up.

Intersestingly, my wife has a nine-year old Subaru that still has its original brakelines and is holding up pretty well down below, I think whatever undercoating they used is quality stuff. Still on the original exhaust, too, which surprises me. I do try and wash the thing, including the undercarriage, one every week or so in the winter, which probably helps.

But the older vehicles like my Dodge, forget it...