Builds Treebeard (2 Viewers)

[Berry]

Hey Nate, hope you're doing well.

I've been driving the wheels off of Treebeard this year—lots of highway miles and lots of trails. With 4WD low and a dream this truck can go anywhere. I'm currently sitting just shy of 340,000 miles (on the truck's odometer) and still going strong. I started diving into a few issues this week that I've been sitting on for a while. These include:

• A soft metallic 'whining' when at highway speeds, coming from the transmission tunnel. The pitch and severity change with throttle position and only appear at 60+ mph.
• An intermittent loud 'thunk' when accelerating from a dead stop. This can be negated by letting out the clutch extremely softly.

After trying (and failing) to pull the transmission and transfer with a floor jack, I admitted defeat and grabbed a dedicated transmission jack. I used the transmission mount and a piece of wood to stabilize the transmission, as recommended here on the forum. Definitely the way to go.

Peeling the transfer apart, I discovered that the transmission output shaft lock nut had completely backed off and was eating into the cover. I'm attributing this to my own idiocy and failing to stake the nut adequately. I believe this is where the 'whining' is coming from. Thankfully, the glitter was well-contained and does not appear to have migrated into the rest of the transfer. Everything else in the transfer looks fine, so I'm planning on replacing the rear bearing, oil seals, lock nuts, cover, gaskets, and reassembling.

As for the loud 'thunk,' I noticed when taking the rear driveshaft off that the rear differential flange has significant play before engaging the axles. Uh-oh. I took the differential cover off this evening and found what appears to be a thrust washer loose in the housing. Also, lots of glitter... No idea how the washer could have made its way out without something catastrophically failing. Additionally, one of the pinions is freely moving on the pinion shaft, with a predictable result. The pinions and side gears are completely ruined.

I'm considering simply scrapping the differential and swapping to a locker. Probably long overdue considering my usage. Please feel free to chime in if anyone has advice relating to these issues. I have a lot of archived threads to read through this evening in order to make an informed decision about the differential.

 

[NookShneer]

Hey Nate, hope you're doing well.

View attachment 3810017

I've been driving the wheels off of Treebeard this year—lots of highway miles and lots of trails. With 4WD low and a dream this truck can go anywhere. I'm currently sitting just shy of 340,000 miles (on the truck's odometer) and still going strong. I started diving into a few issues this week that I've been sitting on for a while. These include:

• A soft metallic 'whining' when at highway speeds, coming from the transmission tunnel. The pitch and severity change with throttle position and only appear at 60+ mph.
• An intermittent loud 'thunk' when accelerating from a dead stop. This can be negated by letting out the clutch extremely softly.

After trying (and failing) to pull the transmission and transfer with a floor jack, I admitted defeat and grabbed a dedicated transmission jack. I used the transmission mount and a piece of wood to stabilize the transmission, as recommended here on the forum. Definitely the way to go.

Peeling the transfer apart, I discovered that the transmission output shaft lock nut had completely backed off and was eating into the cover. I'm attributing this to my own idiocy and failing to stake the nut adequately. I believe this is where the 'whining' is coming from. Thankfully, the glitter was well-contained and does not appear to have migrated into the rest of the transfer. Everything else in the transfer looks fine, so I'm planning on replacing the rear bearing, oil seals, lock nuts, cover, gaskets, and reassembling.

View attachment 3810021
View attachment 3810022

As for the loud 'thunk,' I noticed when taking the rear driveshaft off that the rear differential flange has significant play before engaging the axles. Uh-oh. I took the differential cover off this evening and found what appears to be a thrust washer loose in the housing. Also, lots of glitter... No idea how the washer could have made its way out without something catastrophically failing. Additionally, one of the pinions is freely moving on the pinion shaft, with a predictable result. The pinions and side gears are completely ruined.

View attachment 3810023
View attachment 3810025

I'm considering simply scrapping the differential and swapping to a locker. Probably long overdue considering my usage. Please feel free to chime in if anyone has advice relating to these issues. I have a lot of archived threads to read through this evening in order to make an informed decision about the differential.

Rear differential might still be salvageable. It looks like the thrust washer came out. My guess is when the rear axle semi float bearings/seal were done last.

Common to use grease to hold things in place when but when you slide the axle shafts in things can shift around.

If you pull the diff you could replace them. A diff shop will have left over spider gears from a locker install. Unless you find other things wrong in the diff that need replacing this is something you can do yourself and isn’t very difficult.

Glad to see Treebeard getting after it!

 

[Berry]

Hello again everyone.

The transfer case and differential are back together and installed thanks to a few friends and a harbor freight transmission jack. Treebeard is finally free from daily driver status and I can wrench at a more comfortable pace. I've been fighting low, unsteady vacuum for a few months and a crap idle. As I've replaced, traced, smoke tested, cursed, and plugged every vacuum component on the truck, it's time the intake and exhaust manifolds are removed and machined. And while the carb is out...

Suprise! No secondary action.

I'll be taking a long hard look at the linkages, but I believe the secondary diaphram is the likely culprit. I'm thinking an outstandingly stripped screw kept my carb guy from replacing this last year. Can't say I blame him, it was quite the pain to get out.

Another suprise, look closely at the right side of this last picture. The second (lower) small hole leads to the fuel cut port and is completely obstructed by the gasket and the carb base. Is this an issue? Wrong carb kit? Any help would be much appreciated.

 

[CruiserTrash]

Hello again everyone.

The transfer case and differential are back together and installed thanks to a few friends and a harbor freight transmission jack. Treebeard is finally free from daily driver status and I can wrench at a more comfortable pace. I've been fighting low, unsteady vacuum for a few months and a crap idle. As I've replaced, traced, smoke tested, cursed, and plugged every vacuum component on the truck, it's time the intake and exhaust manifolds are removed and machined. And while the carb is out...

Suprise! No secondary action.

View attachment 3919000
I'll be taking a long hard look at the linkages, but I believe the secondary diaphram is the likely culprit. I'm thinking an outstandingly stripped screw kept my carb guy from replacing this last year. Can't say I blame him, it was quite the pain to get out.

View attachment 3919001

Another suprise, look closely at the right side of this last picture. The second (lower) small hole leads to the fuel cut port and is completely obstructed by the gasket and the carb base. Is this an issue? Wrong carb kit? Any help would be much appreciated.

View attachment 3919002

That gasket actually leaves the vacuum passage open. If your phenolic spacer is in hood shape don’t use the gaskets. If the spacer is in bad shape, well … you’ll have to get creative or find another. I did a thread on the 60 Series carb secondary recently:

Aisin secondary tuning ideas - https://forum.ih8mud.com/threads/aisin-secondary-tuning-ideas.1357784/

 

[Berry]

That gasket actually leaves the vacuum passage open. If your phenolic spacer is in hood shape don’t use the gaskets. If the spacer is in bad shape, well … you’ll have to get creative or find another. I did a thread on the 60 Series carb secondary recently:

Aisin secondary tuning ideas - https://forum.ih8mud.com/threads/aisin-secondary-tuning-ideas.1357784/

Excellent thread @CruiserTrash, thank you for that.

My phenolic spacer has a passage between the two ports so I will omit the gasket as recommended. I've ordered the Edelbrock #12412 spring kit and the NAPA #24093 diaphragm, ideally I'll have updates regarding the paperclip test by next week!