Builds A 13 Year Old and His Future '76 FJ40

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Ok, so I'm glad you said something....so when it was said earlier that he hadn't seen a knuckle that clean ever in a '76, that was a bad thing, not a good thing:) I'll check out that video and make sure we don't engage the 4x4 until we get that knuckle rebuilt

Guys,

I'm afraid I don't agree that lack of oil/grease leaks on the knuckles means the front axle needs to be rebuilt! It could be that someone else already did it or that the seals are simply not leaking. One thing I would do would be to change all the fluids, both axles, steering box, coolant, oil and filters. I'd put her up on jack stands, rotate the wheels, listen for odd noises, see if there's any play in the wheel bearings, etc. No way are you going to destroy anything by putting her into 4 wheel drive and taking it easy to listen to it.

I've had 4 Cruisers in over 30 years and while a couple had nasty front knuckles I've yet to rebuild one although that will change this summer. And I've never had an axle problem front or rear.

Pete
 
Take a look at that driver's side again. It's completely dry. The felt wiper seal should be completely impregnated with grease and constantly wiping grease across the back of the knuckle ball. And grease build up on the back side of the knuckle is not the same as a leak. Certainly he could open the square plug and start squirting moly grease down there but in my opinion there's no better way to become one with your cruiser, mechanically, than to do a knuckle rebuild. :cheers:
 
Take a look at that driver's side again. It's completely dry. The felt wiper seal should be completely impregnated with grease and constantly wiping grease across the back of the knuckle ball. And grease build up on the back side of the knuckle is not the same as a leak. Certainly he could open the square plug and start squirting moly grease down there but in my opinion there's no better way to become one with your cruiser, mechanically, than to do a knuckle rebuild. :cheers:

OK Patrick, maybe I didn't look close enough. But before I'd tell someone who was just getting into Fj40s that they had to do a knuckle rebuild before putting her in 4 wheel drive, I'd at least tell them to drain and replace the axle fluid and to remove the square head plug on the knuckle and see if they could see grease. Reason I suggested putting her on jack stands and listening for unusual noises before tearing into the knuckles is that one thing I've learned is a Cruiser will talk to you about a lot of things and let you know when attention is needed.

Also, I neglected to mention in my previous post - and it should have been at or near the top of the list - is to drain and refill tranny and transfer. My excuse is it was a little after 6AM local time and I wasn't completely awake.

Pete
 
Looks like a great project!! I had a great time with my 15 year old daughter rebuilding the motor on her 2005 VW tdi Beetle. Gotta spend that quality time with them while we can! I HATE the complicated nature of VW tdi's and wish I would've made her get a Toyota. Oh well, she loves it and I get to keep my FJ40 safe in the garage. lol

TK
 
BTW, see if it has the data plate in the engine bay and post up a pic. I'm curious what the original color was on this 40.
So here is the data plate....it's difficult to read though. Pretty sure it says 416 LE11?:)

Data Plate FJ.webp
 
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Guys,

I'm afraid I don't agree that lack of oil/grease leaks on the knuckles means the front axle needs to be rebuilt! It could be that someone else already did it or that the seals are simply not leaking. One thing I would do would be to change all the fluids, both axles, steering box, coolant, oil and filters. I'd put her up on jack stands, rotate the wheels, listen for odd noises, see if there's any play in the wheel bearings, etc. No way are you going to destroy anything by putting her into 4 wheel drive and taking it easy to listen to it.

I've had 4 Cruisers in over 30 years and while a couple had nasty front knuckles I've yet to rebuild one although that will change this summer. And I've never had an axle problem front or rear.

Pete
I think this is great advise...Change all the fluids, listen for funny noises, and see what she tells me. That will be our next project for sure. Thanks again Pete...we are working on it every night (again, little things at first), and my son is eating it up! He is on this forum every night learning about his truck. Tonight he had a question that I didn't know the answer to, and the first thing he said was, "I'll ask Pete":)
 
Thanks but like I said previously, there are many guys on here that know far more than I do about Cruiser and lots of other stuff. I'm just a if it ain't broke don't fix it type and like to take things a little slow. Why? Just have learned the hard way with lots of busted knuckles and lots of good advice from experienced people!

Good luck!
Pete
 
So quick update, and some questions. So we got the all the doors adjusted and working. Replaced all of the felt, and door panels. It all looks nice.

I asked the PO about the knuckles, turns out he had those done just a couple of years ago, so I'm guessing that is why the look so clean?

We are changing out all of the fluids. Next up is Transfer Case and Transmission Fluids. I've looked for some how to videos on this, or some easy instructions on Mud, but haven't found much. I'm sure it's pretty self explanatory, but I like to know for sure what we are doing before we do it:)

Any advise and/or links that we could use for this?
 
PRetty straight forward drain and fill. Watch the t case if its full past the drain plug then you have a leaky seal between the trans and transfer case. Not a huge issue but it allows the fluid to drain into the t case. There is a bypass hose you can get but that guys run to help the fluid drain back in once its over full.
 
Sounds like things are going great jayster! Changing the transmission and transfer fluids is pretty easy but messy. I always like to get things warmed up a bit because that gear oil is like molasses when cold but even stickier! Both the tranny and transfer have drain plugs on the bottom so you just remove those and let her drain. Be careful not to drop or loose the bronze washers. Actually before removing the plugs while you're under there, see if there seems to be a LOT of gear oil all over the place. What can happen and it's not unusual is for the gasket between the transfer and transmission to fail and the gear oil runs from the transfer down to the transmission and leaves the transfer dry which leads to failure of the transfer. The excess oil in the transmission gets forced out the breather and spread all over the place. You can also look at how much gear oil comes out of the transmission and transfer case when you drain them. if there's a lot more out of the transmission than its capacity (I forget what the capacity is, a couple of quarts?) and the transfer drains almost nothing, you might have that leak. What I've done on my rigs after I lost the transfer on my '71 by letting it run dry is to install an overflow hose between the transfer and transmission. Even on a later rig with no leak I put the hose in as an emergency back-up. Spector used to sell a rubber hose kit but a couple of years ago someone here on mud was selling some nice braided stainless ones and I got one of those for my '78. I'm not saying you should put the hose on but it's relatively cheap insurance.

After both are drained, put the drain plugs with washers back in and be careful not to cross thread or over-tighten. Remove the fill pugs on the sides of both and fill with gear oil until the level reaches the bottom of the fill hole. Make sure the rig is level. The hardest part of this job, for me at least, has always been filling he transfer and tranny because as I said that gear oil is like molasses and you can't just pour it in. I've tried the cheap Harbor Freight plastic hand pumps which are not worth it even if they are cheap. So I just use the plastic bottles which I think are half gallon size with a length of clear plastic tubing and squeeze the gear oil in.

I think the manual calls for something like 90 or 95 weight gear oil which you don't see much of in your Auto Zone or typical parts store that seems to normally have 85W90 or 90W95. I've used the multi-grade for years with no problems, just the heaviest I can find.

Good luck!
Pete
 
FLAPS should have clear PVC tube that will screw onto to your gear oil bottle. Hold bottle parallel to ground and up near fill hole. Squirt gear oil in fill hole until it almost runs out fill hole.

BSEVANS Bypass hose thread —> link
 
Sounds like things are going great jayster! Changing the transmission and transfer fluids is pretty easy but messy. I always like to get things warmed up a bit because that gear oil is like molasses when cold but even stickier! Both the tranny and transfer have drain plugs on the bottom so you just remove those and let her drain. Be careful not to drop or loose the bronze washers. Actually before removing the plugs while you're under there, see if there seems to be a LOT of gear oil all over the place. What can happen and it's not unusual is for the gasket between the transfer and transmission to fail and the gear oil runs from the transfer down to the transmission and leaves the transfer dry which leads to failure of the transfer. The excess oil in the transmission gets forced out the breather and spread all over the place. You can also look at how much gear oil comes out of the transmission and transfer case when you drain them. if there's a lot more out of the transmission than its capacity (I forget what the capacity is, a couple of quarts?) and the transfer drains almost nothing, you might have that leak. What I've done on my rigs after I lost the transfer on my '71 by letting it run dry is to install an overflow hose between the transfer and transmission. Even on a later rig with no leak I put the hose in as an emergency back-up. Spector used to sell a rubber hose kit but a couple of years ago someone here on mud was selling some nice braided stainless ones and I got one of those for my '78. I'm not saying you should put the hose on but it's relatively cheap insurance.

After both are drained, put the drain plugs with washers back in and be careful not to cross thread or over-tighten. Remove the fill pugs on the sides of both and fill with gear oil until the level reaches the bottom of the fill hole. Make sure the rig is level. The hardest part of this job, for me at least, has always been filling he transfer and tranny because as I said that gear oil is like molasses and you can't just pour it in. I've tried the cheap Harbor Freight plastic hand pumps which are not worth it even if they are cheap. So I just use the plastic bottles which I think are half gallon size with a length of clear plastic tubing and squeeze the gear oil in.

I think the manual calls for something like 90 or 95 weight gear oil which you don't see much of in your Auto Zone or typical parts store that seems to normally have 85W90 or 90W95. I've used the multi-grade for years with no problems, just the heaviest I can find.

Good luck!
Pete
Hey Pete, thanks again for your help! Ok so the tranny/transfer case definitely are covered in grease and grime. With what you said, it sounds as if that gasket between the 2 has indeed failed. So my first question is should we make it a priority to replace that seal, or should we simply install that hose kit. I'm sure at some point in the future we will have the tranny rebuilt, at which point we would have that gasket replace, but that is some time in the future. Thoughts?
 
Hey Pete, thanks again for your help! Ok so the tranny/transfer case definitely are covered in grease and grime. With what you said, it sounds as if that gasket between the 2 has indeed failed. So my first question is should we make it a priority to replace that seal, or should we simply install that hose kit. I'm sure at some point in the future we will have the tranny rebuilt, at which point we would have that gasket replace, but that is some time in the future. Thoughts?

I don't think I'd make the decision until I drained the transfer case to see how much gear oil you got out of that. If it's quite a bit and close to the capacity, I might just go with the hose. If it's bone dry, then you might want to replace the seal. It's normal to see some oil on the outside of the transmission because there's a breather on top (at least on the ones I've seen) that will allow some oil out. Replacing the seal is a pain and some will probably tell you that you need to pull the transmission and transfer out of the rig. It's been years ago when my transfer ran dry and seized up so that I had to do some major surgery. I can't recall if I pulled only the transfer or the transfer-transmission together but I think I was able to pull the transfer alone. Others will chip in on this I'm sure. I replaced the main shaft and a couple of the gears and all seals once I had it out. I did this in my gravel driveway without a good floor jack so it wasn't fun.

Pete
 
416 is dune Beige,, Cool color..
dunefj.webp
 
Sounds like things are going great jayster! Changing the transmission and transfer fluids is pretty easy but messy. I always like to get things warmed up a bit because that gear oil is like molasses when cold but even stickier! Both the tranny and transfer have drain plugs on the bottom so you just remove those and let her drain. Be careful not to drop or loose the bronze washers. Actually before removing the plugs while you're under there, see if there seems to be a LOT of gear oil all over the place. What can happen and it's not unusual is for the gasket between the transfer and transmission to fail and the gear oil runs from the transfer down to the transmission and leaves the transfer dry which leads to failure of the transfer. The excess oil in the transmission gets forced out the breather and spread all over the place. You can also look at how much gear oil comes out of the transmission and transfer case when you drain them. if there's a lot more out of the transmission than its capacity (I forget what the capacity is, a couple of quarts?) and the transfer drains almost nothing, you might have that leak. What I've done on my rigs after I lost the transfer on my '71 by letting it run dry is to install an overflow hose between the transfer and transmission. Even on a later rig with no leak I put the hose in as an emergency back-up. Spector used to sell a rubber hose kit but a couple of years ago someone here on mud was selling some nice braided stainless ones and I got one of those for my '78. I'm not saying you should put the hose on but it's relatively cheap insurance.

After both are drained, put the drain plugs with washers back in and be careful not to cross thread or over-tighten. Remove the fill pugs on the sides of both and fill with gear oil until the level reaches the bottom of the fill hole. Make sure the rig is level. The hardest part of this job, for me at least, has always been filling he transfer and tranny because as I said that gear oil is like molasses and you can't just pour it in. I've tried the cheap Harbor Freight plastic hand pumps which are not worth it even if they are cheap. So I just use the plastic bottles which I think are half gallon size with a length of clear plastic tubing and squeeze the gear oil in.

I think the manual calls for something like 90 or 95 weight gear oil which you don't see much of in your Auto Zone or typical parts store that seems to normally have 85W90 or 90W95. I've used the multi-grade for years with no problems, just the heaviest I can find.

Good luck!
Pete

What Pete says in here is good. There is only one thing I would add. Before you drain the gear oil from transmission, transfer case, or differentials, MAKE SURE that the fill plugs can be loosened. It can be very difficult to put oil back in when the oil is drained first, and then discover you have problems with the fill plug and need to put oil in.

Don
 
What Pete says in here is good. There is only one thing I would add. Before you drain the gear oil from transmission, transfer case, or differentials, MAKE SURE that the fill plugs can be loosened. It can be very difficult to put oil back in when the oil is drained first, and then discover you have problems with the fill plug and need to put oil in.

Don

Excellent point Don, I should have said that. I've never had the problem myself with a frozen fill plug but I know it can happen.

Pete
 
I've never had that problem either. But, it is something I try to remember now since learning about the problem from those that have been there.

Don
 

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