Topic: Blackdiamond (Gup-C build-up)

[blackdiamond]

Carl figured that he should take a look inside the Detroit Locker before putting things back together and discovered some wear on a spacer and what appears to be a missing bevel spring that apparently was never part of the assembly from new.  He has reached out to some others on a Gear Install Technical Group to confirm his thinking.  It appears that he found a replacement part from Just Differentials for $8 and he doesn't think the wear will create any longterm issues.  An $8 part is certainly better than a new locker!

[Gnarly4X]

Would Carl say that what he is seeing in more like normal wear, premature failure due to defect, improper original installation, failure caused by bent axle housing or components, or caused by a lack of maintenance issue?

Gnarls.

[blackdiamond [OP]]

Would Carl say that what he is seeing in more like normal wear, premature failure due to defect, improper original installation, failure caused by bent axle housing or components, or caused by a lack of maintenance issue?

Gnarls.

I have not had a chance to chat with him much about it, but based on video he posted on the FB group it appears that my locker was missing an internal part that allowed the plate to shift and make contact with another part resulting in the wear. I think he planning to replace the spring washer and expects it to function as designed.

If you’re talking about the overall state of things I don’t have any idea.

[blackdiamond [OP]]

It sounds like a replacement for the missing piece of the Detroit has been ordered. Now I can just hope that all of the parts will assemble without any further curiosities.

https://www.justdifferentials.com/DET70759-p/det70759.htm

[blackdiamond [OP]]

Carl was able to get an initial pattern with the new gears so the 3rd member seems to be ok. Just waiting for the missing part to arrive before what should hopefully be final assembly.  The missing piece is part of the “soft locker” assembly, so the might find that things are smoother with it working correctly for the first time since 2003.

[Gnarly4X]

It was installed in the 3rd around 2002. I doubt that installer wouldn’t have caught this issue since he was super picky.

Was the Detroit SL installed the same time the 3rd was installed?

Gnarls.

[blackdiamond [OP]]

Was the Detroit SL installed the same time the 3rd was installed?

Gnarls.

The 3rd was built with the Detroit locker and 4.88 gears in 2002 or 2003 for my ‘85 truck. The build 3rd was simply swapped into the late model housing for my ‘89 4Runner build. I’m sure the Detroit was never opened up prior to this adventure.

[blackdiamond [OP]]

Here is the initial pattern with the new gears.

[blackdiamond [OP]]

It’s done and I’ll be picking it up after work today.

[Gnarly4X]

It’s done and I’ll be picking it up after work today.

Hey b....

I'm so glad you are finally getting to drive your vehicle again.

Could you detail what ALL was done? 

Gnarls.

[blackdiamond [OP]]

I picked up the 4Runner today after work and drove it home slowly and carefully since I'm breaking in the new ring and pinion.

- The rear housing was straightened.  It was bent fairly significantly.
- The axle bearings were replaced.  Once was bad and the other on the way out.
- The pinion and carrier bearings were replaced.  They had evidence of junk going through them at some point.
- The ring and pinion were replaced.  The pinion had a burr on one tooth and cracks in three others.  The ring gear also had at least one crack.  To the naked eye only the burr is visible, but they didn't setup quite right.
- The Detroit locker was rebuilt adding the missing belleville springs washer that seems to have been missing from the factory.

I only got it up to 60 mph for a very brief period of time and it seems that the wild vibration is gone, but being a 30+ year old vehicle it still has a lot of creaks and groans, so I didn't come home with a new feeling vehicle.  The rear differential feels tighter and the locker seems to be smoother though it's hard to really know at this point.  It'll be getting driven a lot more in the near future.  I'll probably put it on jack stands and verify that the vibration is 100% gone for my own peace of mind.

[Gnarly4X]

Hey b....

I would think that with your added equipment, your Runner is well over 4,000 lbs.

Have you weighed it and know what the weight is? 

Gnarls.

[blackdiamond [OP]]

Hey b....

I would think that with your added equipment, your Runner is well over 4,000 lbs.

Have you weighed it and know what the weight is? 

Gnarls.

I have never put it on a scale. Why?

[Gnarly4X]

I have never put it on a scale. Why?

I was thinking that the added weight would put extra stress on the powertrain, possibly causing premature drive train component failure.

Or... unexpected rear axle housing damage.

The GVWR (Gross Vehicle Weight Rating) minus the Curb Weigh (what it weighed ready to drive off the dealer's lot) = payload capacity (whatever added weight).

Towing Capacity = 3306 (according to Carsguide)
1989 4Runner Curb Weight = 3,760 lbs. (according to Wikipedia)

I could not find the GVWR of a 1989 Toyota 4Runner.

I doubt that the GVWR has been exceeded by the extra weight that has been added to the vehicle.

Gnarls.

[blackdiamond [OP]]

On the way to work this morning I was able to get the 4Runner above 60 mpg for a bit and it seems that thing really smooth out above 60 mph, but there’s still something happening in the 50-60 mph range that’s less than ideal.  At least it seems to be fairly solid at highway speeds now.

[blackdiamond [OP]]

Carl is thinking that I most likely have a metal to metal contact point causing the current vibration. T-case mount, body mount, exhaust, etc.  I’ll have to find some time to do some looking.

For now, there’s enough other things in play that the 4Runner is most likely out for this years Moab trip. It’s not absolutely needed for our trip to be successful.

[LittleSteve]

Carl is thinking that I most likely have a metal to metal contact point causing the current vibration. T-case mount, body mount, exhaust, etc.  I’ll have to find some time to do some looking.

For now, there’s enough other things in play that the 4Runner is most likely out for this years Moab trip. It’s not absolutely needed for our trip to be successful.

I'd say it was decidedly more up together than my first gen was for the rubicon trip.

[blackdiamond [OP]]

I'd say it was decidedly more up together than my first gen was for the rubicon trip.

From what I know about that trip I would have to agree. One significant difference is that you are far more suited for repairs along the way.  Trail repairs are not my cup of tea.

If this was a typical “boys” trip where the harder wheeling was the goal I’d probably risk it, but this trip is family wheeling centric so it’s just not worth it.

[LittleSteve]

From what I know about that trip I would have to agree. One significant difference is that you are far more suited for repairs along the way.  Trail repairs are not my cup of tea.

If this was a typical “boys” trip where the harder wheeling was the goal I’d probably risk it, but this trip is family wheeling centric so it’s just not worth it.

By trail repairs you mean holding the transmission in with a ratchet strap round the sliders and changing a tyre?  The transmission waited till we got back before it grenaded   

[Gnarly4X]

By trail repairs you mean holding the transmission in with a ratchet strap round the sliders and changing a tyre?  The transmission waited till we got back before it grenaded   

Geeezzz... Over the many years I wheeled, I have seen "trail repairs" that were nothing short of amazing!

On the downside..... half of them were the consequence of stupidity or inexperience.

Gnarls.

[LittleSteve]

Geeezzz... Over the many years I wheeled, I have seen "trail repairs" that were nothing short of amazing!

On the downside..... half of them were the consequence of stupidity or inexperience.

Gnarls.

What can I say? Crossmember broke off.. wasn't of my making nor was it original and the tyre well, I guess rocks can be sharp.. the G series tranny was howling on the way there and on the way back soooo...

[blackdiamond [OP]]

I put the 4Runner on jackstands this morning and the vibration seems to steadily increase with speed instead of before when things got wild above 50 mph.  I took videos of both ends of the driveshaft and along the driveshafts length and I don’t see any obvious vibration movement.  Next I’ll look for contact related vibrations.

[Gnarly4X]

Geezzz... BD... have you been generating some really bad Karma??

Gnarls. 

[LittleSteve]

I put the 4Runner on jackstands this morning and the vibration seems to steadily increase with speed instead of before when things got wild above 50 mph.  I took videos of both ends of the driveshaft and along the driveshafts length and I don’t see any obvious vibration movement.  Next I’ll look for contact related vibrations.

Youve checked all the UJ's? Im going to assume it has no center besring?
Gear man checked the axle shafts for straightness?
The output of the tcase has no play?
Youve not lost any balance weights off the driveline?

[blackdiamond [OP]]

Youve checked all the UJ's? Im going to assume it has no center besring?
Gear man checked the axle shafts for straightness?
The output of the tcase has no play?
Youve not lost any balance weights off the driveline?

The CV driveline is freshly rebuilt with new joints and balanced. Nobody has noted any play at the t-case output.

[Gnarly4X]

Of course the "phasing" has been verified.

Gnarls.

[EASYRYDERDANGER]

Didn't read too far back, but you try getting your tires balanced or rotating them?

[blackdiamond [OP]]

Of course the "phasing" has been verified.

Gnarls.

I’d say yes in that it hasn’t been changed from when it was rebuilt and balanced. I’m not sure if you can really cause a phase issue with a CV style anyways.

[blackdiamond [OP]]

Didn't read too far back, but you try getting your tires balanced or rotating them?

I eliminated tires in multiple different ways prior to the rear end repairs, so it’s possible that they are contributing to the remaining vibration. I think I am working through multiple independent issues with overlapping symptoms. The worst of the vibrations is resolved, but now the secondary issue needs to be fixed.

My time when I’m motivated has been limited, so it’ll be a few weeks before I dig into it again.

[EASYRYDERDANGER]

Atleast you can go down the road now with less worries.  Got a question about your rear "tracbar" or axle wrap bar, you have any good suggestions on making/buying one?  I've noticed my rear leafs are super soft and daily driving on/off the gas results in alot of wind up.  I can actually watch the axle rotate a little by pushing back n forth on the truck with parking brake on.