Birfield Question.....

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The entire back side of ball should be a little greasy and oily. It's a "total loss" type lubrication system. The felts and wipes are there to keep the grease "contained" and not just flowing out all over, but you have to top off the knuckle ball with grease. I give mine about 35ML every 7500 miles, when I do all the other regular maintenance. Looking at yours, it appears you only have grease about half way up the ball, but it could be the lighting.
Grease, by its nature is an oil suspended in a carrier. When grease gets warm the oil flows out of the carrier and when it cools the oil goes back into the carrier. The drip of oil off the bottom of the knuckle bolts is totally normal.
Ok, I will open the port tomorrow and check the level with a zip tie. I have a tube of dark grey Toyota moly CV joint grease. Is that the right stuff or should I just go buy a cartridge of moly fortified lithium grease?
 
I use Moly EP grease out of a tub. Valvoline, or STP probably. I use a turkey baster marinade injector with the needle removed to measure in a known amount.
 
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I use Moly EP grease out of a tub. Valvoline, or STP probably. I use a turkey baster with the needle removed to measure in a known amount.
Ok, I will cobble something together.....part of this is figuring out what tools & supplies go with the car to Denver.
 
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This is driver's side, pax side matches. Thumb is the top of the inspection port. I suspect that I ned to raise the level to a point halfway between where it is and where my thumb is, but I would appreciate confirmation from someone.
 
My opinion, add 75ml of grease, clean the back side of the balls thoroughly and drive it for a week. Then look at the back side and see where the oil streak is. Add more grease as needed to bring up the level so the back of the balls are uniformly oily.
 
You mentioned the harmonic balancer is split and nobody seems to have caught that. That is a show stopper that will damage the engine quickly if it fails, so replace it.
 
@IdahoDoug Great catch, I also missed that. I recently had to replace my HB due to the outer ring moving independently of the inner portion. I only noticed it when setting the timing gears after a new head gasket. With the chain and sprockets all aligned the HB timing mark was at the 4 O'clock position.
Like all the other rubber on these 30 year old trucks the HB is likely due for a refresh.
 
You mentioned the harmonic balancer is split and nobody seems to have caught that. That is a show stopper that will damage the engine quickly if it fails, so replace it.

I had a whole pile of help on fixing the HB and did a bunch of other logical "while you are there things as well"

Thanks to all
 
Ok, it has been about 500+ miles since I topped off the grease for the birfield and cleaned up 30 years of dirt. I took this picture of the Driver's side from the rear as the wheel was off to do the starter. Pax side is similar. The truck has 235k of 98% highway driving to a cabin in the woods as its history.

There is no clicking noise accelerating, turning or going straight. The joints have not been serviced. Any thoughts? We are pretty deep into a maintenance baseline as part of handing this down to my daughter and I am torn over what to do here


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Some moly grease on the ball is normal over time, but that looks slightly soupy/mixed to me. As always, I could be wrong. Probably one of those things where it may time to do the job, but it's still functioning normally at present.

I hadn't read most of this thread, but just skimmed and I see you addressed the breather, so you wouldn't expect that to be a cause of mixing.
 
Some moly grease on the ball is normal over time, but that looks slightly soupy/mixed to me. As always, I could be wrong. Probably one of those things where it may time to do the job, but it's still functioning normally at present.

I hadn't read most of this thread, but just skimmed and I see you addressed the breather, so you wouldn't expect that to be a cause of mixing.
I am torn. The diff oil seemed free of grease when I changed it. The smell is something I won't forget but I doubt there would be enough on the ball to make an impact to my nose. When I did the rear wheel bearings, it was clear the seals were shot and the bearings were running on diff oil. The front seals are different but....

The goal is to hand off a relatively trouble free car, I fear I am going to be getting dirty ....

Thanks for your time, I have gone through the OTRAMM video plus a couple from Australia.
 
My guess is that in your case, this is a service, rather than a "repair." Always the nicer side to be on.

I'm certainly no expert, but I don't think you'll always have mixing in both directions. Gear oil could be sneaking past the seals into the knuckles, and then the knuckles leak slightly past the wipers - but moly grease may not be sneaking the other direction into the diff, thus the gear oil may not be the best gauge. Just some food for thought (and I'm always open to peoples thoughts on this/anything)

I wasn't handing my truck off, but was in a similar position during my baselining. I noticed mixing/leaking on the balls, but wasn't having any functional issues. Started planning for the job, and got to it when I could.

You're always going to get dirty with an older vehicle, no matter how good they are!

RE: videos - I liked 2nd gear low from AUS, OTRAMM of course, and I thought 6th gear garage was great as well. Between those and collective knowledge here on the forum, I felt super/over prepared by the time I did it.
 
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I would do the service it’s overdue.
If you’re sure it’s never been done Why are you hesitating?
 
I would do the service it’s overdue.
If you’re sure it’s never been done Why are you hesitating?
The original owner (my father) does not think it is necessary.....very ex railroad guy. I have the service records - front hubs done every 30k miles. No indication from descriptions or invoice amount that the full axle service was ever done.

Sort of torn between wanting to be done with this refresh with this and knowing it should be done well.
 
With the mileage it has, i would be leaning toward doing it.
Not just for the sake of fresh seals, or fresh birfs, but so you can put in new trunion bearings too.
I've seen trunion bearings completely toasted at around 150k miles.

Fresh trunion bearings along with tie rod ends, fresh wheel bearings, fresh bushes all contribute to nice sharp steering feel.
 
If not 100% necessary now, you're on borrowed time.

Do it now when you're doing it in a place and time if your choosing, not in desparation due to failure later

Also, add refreshing of knuckle studs and nuts to the list of safety items to address at time of your choosing.

Remove, clean, inspect, reinstall, or replace or upgrade all knuckle studs, washers, nuts.
 
Yes, the front bearings have been on an every 30k mile service program since new, they are 20k since the last service.....

Frankly, I have some time and this will be among the last items on my list. Rear bearings have never been serviced, but seem fine so I will start with them.

Parts are stacking up and I need to create a more detailed work plan. My immediate goals:

- Take as is photos.
- Figure out "all rubber" approach to rear heater
- Drain coolant - radiator hose and block.
- Drain and fill transmission pan
- Disassemble rear heater valve, EGR, throttle body and IM
- Have IM cleaned professionally
- Remove starter
- Replace all transmission, cooling, heating hoses as well as vacuum lines.
- R&R rear bearings

Rotors were done at 154k miles, the fronts are suspect to me. There is a sort of depression in the left front uniformly 3/4" wide. Brakes are on the list, we have done the lines and fluid. Delaying a bit on pads and rotors.
If you're replacing wheel bearings every 30k, you are God's gift to parts sellers. I know that may be recommended, but the front wheel bearings, driven primarily on the road, while last thousands of miles. Mine have. I wouldn't worry about them unless they're loose.
 
The "front axle rebuild" as may have been mentioned above (I can't remember and I'm not looking back) is a rear rubber and felt seal replacement, along with new grease. You're not "rebuilding" anything. You said the front axle service had been done every 30k miles. What's a "service"? Replacing wheel bearings (and hopefully seals)?

If so, whoever did that would have noticed a mixture of bearing grease and gear oil then. It's very obvious. As to getting grease in the differential gear oil, I don't think you'd see it, if you didn't know what you were looking for; it migrates the other way, towards the wheel, so you wouldn't see a bad inner wheel seal there.

FWIW, if I was doing a front wheel "service", I'd inspect the wheel bearings after cleaning them and if they looked OK, I'd repack them with grease and replace the inner and outer seals and the gasket under the drive flange. I also always replace the cone washers, unless I know they have been replaced within 50k or so (and the nuts, if the corners are rounding). But that's just me.

The knuckle seals and felts, along with chassis lube points, are supposed to be replaced, inspected or lubricated (dealer's choice, no pun intended) every 24 months; wheel bearings and seals every 36 months, according the Maintenance Schedule "B", which is the on-road everyday use schedule. Dealerships take the "replace" option, because that's how they stay in business. I'm like your dad (I used to design railroad maintenance equipment); I choose "inspect" and "lubricate" first, and "replace" if necessary.
 
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...and, for the sake of clarity,
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