TrailTips: Broken CV

[lockedlex]

I'm a moderator on a BMW Board and occasionally, we have these TechTip posts where we discuss hypothetical or theoretical circumstances and what drivers would do (like how do you do a J turn w/ an electronic handbrake that you can't modulate, etc).

So let me switch it up and call it TrailTips and start off by posing this question.

What would you do if you're on a trail and you snap a front CV?

1) You happen to have all the tools to pull out the broken CV, but no spare CV.
2) You have no tools at all. Is there anything you can do to limp your way home (let's assume the trail is now just a flat dirt road, not having to climb up things).

I'll move things along and maybe ask some questions to any follow up and anyone else can too, but the hope is having an on-point discussion that would help someone know how to handle something without maybe sifting through 20 pages.

 

[nobb]

In both your scenarios I would probably find a way to secure the CV so that it's not flapping around and damaging surrounding parts, and just limp away in 2WD. If the trail is REALLY bad and 4WD is necessary to get home, then the only option would be to try to get a ride/walk to get parts/tools or try to get towed out.

If you're going somewhere very remote, I would carry a spare CV, tools, spare LBJ's, an UBJ, and a spare brake hose + brake fluid. LBJ failure will cause failure of all these parts. The UBJ would be a pain in the ass to replace in the field so maybe also a ball joint removal tool too.

 

[sleepydad]

I'm a moderator on a BMW Board and occasionally, we have these TechTip posts where we discuss hypothetical or theoretical circumstances and what drivers would do (like how do you do a J turn w/ an electronic handbrake that you can't modulate, etc).

So let me switch it up and call it TrailTips and start off by posing this question.

What would you do if you're on a trail and you snap a front CV?

1) You happen to have all the tools to pull out the broken CV, but no spare CV.
2) You have no tools at all. Is there anything you can do to limp your way home (let's assume the trail is now just a flat dirt road, not having to climb up things).

I'll move things along and maybe ask some questions to any follow up and anyone else can too, but the hope is having an on-point discussion that would help someone know how to handle something without maybe sifting through 20 pages.

I unlock my manual locking front hub and keep going.

<a href="https://imgur.com/kt3PYjS"><img src="https://i.imgur.com/kt3PYjSl.jpg" title="source: imgur.com" /></a>

 

[Andy in Pa]

I unlock my manual locking front hub and keep going.

<a href="https://imgur.com/kt3PYjS"><img src="https://i.imgur.com/kt3PYjSl.jpg" title="source: imgur.com" /></a>

And put it in 2wd? Because if not, you're still spinning the CV.:nod:

 

[my92t4r]

I'll Flintstones it home

 

[sleepydad]

And put it in 2wd? Because if not, you're still spinning the CV.:nod:

 

[rkntoy]

1 - Pull the cv and pull the inboard end off. Stuff it back in the diff so the gear oil doesn't leak out and drive home after unlocking hub on that side.

2 - Easy. Flat dirt road means unlocking hub and putting it in 2wd. Without manual hubs if you break the outboard cv cage you can cut the boot and pull it apart leaving the outboard end in the knuckle. The do the same with the inboard end and leave it in the diff.

 

[lockedlex]

1 - Pull the cv and pull the inboard end off. Stuff it back in the diff so the gear oil doesn't leak out and drive home after unlocking hub on that side.

2 - Easy. Flat dirt road means unlocking hub and putting it in 2wd. Without manual hubs if you break the outboard cv cage you can cut the boot and pull it apart leaving the outboard end in the knuckle. The do the same with the inboard end and leave it in the diff.

I didn't know 3rd gens came with manual hubs? I don't believe mind has them.

Regarding #2, I think I see what you mean, So if something internal snaps sufficiently, you can pull off the boots then pull out the remaining parts?

 

[tx_shooter]

I didn't know 3rd gens came with manual hubs? I don't believe mind has them.

Regarding #2, I think I see what you mean, So if something internal snaps sufficiently, you can pull off the boots then pull out the remaining parts?

1 - It is a less common mod to swap the auto hubs with manual hubs. 3rd gen did not come factory with manual hubs.

2 - yes. If you disassemble the CV you can secure the different ends in their respective position to get off the trail.


Just a word of advise - the trail is not the place to learn to swap a CV. If you have never done one I would advise finding someone who is going to swap one in a controlled setting and buy them a few beers so you can watch. It is not hard but not something you want to do for the first time in a bad environment.

 

[kolelt]

I didn't know 3rd gens came with manual hubs? I don't believe mind has them.

Regarding #2, I think I see what you mean, So if something internal snaps sufficiently, you can pull off the boots then pull out the remaining parts?

They didn’t. People modify it.

 

[sleepydad]

I didn't know 3rd gens came with manual hubs? I don't believe mind has them.

Regarding #2, I think I see what you mean, So if something internal snaps sufficiently, you can pull off the boots then pull out the remaining parts?

1st gen tacoma trucks base model came with manual hubs. the steering knuckle, bearing are the same part number between 3rd gen 4runner and 1st gen tacoma.

cv axles are different spline counts 26 on taco, 30 on 4runner on the hub side but diffs are 30 splines.

so it's really not a mod, more of a parts swap.

I remember back in the old days thinking how cool the ADD hubs were and then I had to do a CV rip out on the trail in a mud puddle. the cool factor was gone and I was always looking for a way to get back to the good old days. I totally get it the ADD hubs are so much easier to service but... the manual hubs have it where it counts in versatility IMO.

 

[rkntoy]

I didn't know 3rd gens came with manual hubs? I don't believe mind has them.

Regarding #2, I think I see what you mean, So if something internal snaps sufficiently, you can pull off the boots then pull out the remaining parts?

You swap them in from base model 1st gen Tacomas.

For #2 - usually you break the cage that holds the bearings. Most of the time you break it enough that you can separate the shaft and remainder of the cage from the outside part of the cv that goes through the knuckle.

 

[RonJR]

If you don't have manual hubs, you probably have drive plates, which are pretty much just like manual hubs without the switching mechanism. They connect the splined end of the CV axle to the wheel hub. You can just pull these off by undoing the six small nuts around the center of the hub (not the lug nuts) and then breaking loose the conical washers (not necessarily easy, try googling this). Duct tape part of a trash bag over the open axle to keep out dirt, and you will be driving in 2wd with no CV's turning. A poor man's manual hub, so to speak.

 

[phattyduck]

If you don't have manual hubs, you probably have drive plates, which are pretty much just like manual hubs without the switching mechanism.

Nope, that's not how the IFS hubs are on the ADD trucks and 4Runners. The whole hub is splined and there is no drive plate. The outer axle needs to stay in place to keep the wheel bearings pre-loaded, so that can't be removed to drive more than a few feet.

-Charlie

 

[rkntoy]

Nope, that's not how the IFS hubs are on the ADD trucks and 4Runners. The whole hub is splined and there is no drive plate. The outer axle needs to stay in place to keep the wheel bearings pre-loaded, so that can't be removed to drive more than a few feet.

-Charlie

This. They even drew the splines in on the picture I threw in.

One more benefit of the manual hubs is that they have a big nut that retains bearing preload if you pull the whole CV out.

 

[RonJR]

Nope, that's not how the IFS hubs are on the ADD trucks and 4Runners. The whole hub is splined and there is no drive plate. The outer axle needs to stay in place to keep the wheel bearings pre-loaded, so that can't be removed to drive more than a few feet.

-Charlie

Ah, my bad. That's a change from the 2nd gen ADD trucks. I (wrongly) assumed the 3rd gens were the same.

 

[JZiggy]

If you don't have manual hubs, you probably have drive plates, which are pretty much just like manual hubs without the switching mechanism. They connect the splined end of the CV axle to the wheel hub. You can just pull these off by undoing the six small nuts around the center of the hub (not the lug nuts) and then breaking loose the conical washers (not necessarily easy, try googling this). Duct tape part of a trash bag over the open axle to keep out dirt, and you will be driving in 2wd with no CV's turning. A poor man's manual hub, so to speak.

The 86-95 4Runners were like this. If the 96+ 4Runners were too then the manual hub swap would literally be as easy as installing hubs. But it's not.

 

[RonJR]

Yeah, I was disappointed to find on my 4th gen that Toyota had abandoned the tried and true, easily serviced, tapered roller bearings and gone to a much more difficult to replace pressed-on sealed bearing assembly. I didn't realize they had made that change on the 3rd gens already.

The old-style tapered roller bearings are so easy to service, and will run forever if kept lubed properly. I can't see that my life is better because of the change. Must have been a manufacturing issue.