I have a couple questions on my differential rebuild. I highjacked another thread, so here is a fresh one. I'm working on a '15 touring car.

Question 1: I took my differential apart and found that the thrust washer on one side had worked itself off the allignment pin and most of the outer steel washer was eaten away from the axle rubbing on it. I am leaning toward the new type bearings to replace the bronze thrust washer assy. Any thoughts on this?

Question 2: My diff. is completely dissasembled except for the carrier. Should I tear into it as well? I found the above problem, plus the inner bearings were worn and pitted. What should be checked out inside the carrier and if there is a problem, what could I do about it? I am a young, first time model T restorer and don't want to get in over my head, plus I know the current tally to get the diff and driveshaft back together is around $500

One response from the other thread...

Grant,Here is one thing to be aware of.If you have a pre'17 rear end the thrust plate pins are just that-straight pins.To use the '17 and later stepped oin p/n2531B you will have to drill out the old pin hole to fit the later pins.I usually do this as the early pin hole has be wallered out.The other option is to make a pin out of drill rod,fitting required.As far as inside the differential goes,there is a[usually red] fiber washer about the size of a quarter,p/n2506,that goes between the axles.This requires complete disassembly. Without actually seeing your bearings,etc,it is tough to determine if you can use what you have.Now to fire up a controversy.My only experience with some sort of ball or radial roller thrust washers is to pull a friend back to his place.This was accomplished by removing both rear wheels,taking out the axle keys,greasing hell out of the axle and putting the wheels back on with no key.Reason for this was dozens of little balls or rollers floating around in the diff case locking everything up.Of course all the gears got chewed up in this process.A very unsuccesful first run.I can still see Ron Knepper in my rear view mirror, cussing,as I pulled him slowly home.

All the bearings and sleeves will have to be replaced.

How crucial is the fiber washer between the axles? ie. Is it worth going in to replace it?

The little fibre washer between the ends of the axles controls the mesh of the differential gear on the end of the axle and the gears on the spider.These are the gears that actually propel the car.I can not imagine why anyone would rebuild a rear end without replacing this.Or for that matter inspecting the differential spider and gears.If your inner roller bearings are badly worn,there is a good chance of issues within the differential case.Worn inner bearings are indicative of a lack of lubrication sometime in the last nine or so decades. A dry rear end usually means spider gear wear.

The Bronze thrust washers for the rear end do NOT crumble - ever. They might wear eventually but they have never once failed catastrophically - that I am aware of. The babbit versions have a really bad track record in modern times of simply going all to pieces all of a sudden. Whether this is due to age or in fact that they are not truly babbit as has been discussed - I simply don't know. The needle bearing versions are something I have zero experience with personally but have a few friends that tried them and had to redo their rear ends afterward when they failed. It is difficult to calculate the load on those bearings since it occurs when the T makes a corner and the amount of thrust is determined by the weight of the car and the speed and angle of application...etc. I am not sure how you set the clearance with those devices being used as thrust washers but with bronze thrust washers you simply sand them off or cut them someway to set the clearance up perfectly. Perhaps others who actually have used those needle bearing devices could post their experience and for myself I would like to know, when using those devices, how the clearances are adjusted for proper end play and gear mesh etc. A very good mechanic friend of mine who shall remain nameless, used to use those a lot when they first came out but then said he doesn't use them any more and he never elaborated as to why and I would like to know the whole story myself. It is entirely possible that the needle bearing thrust washers failed because they were not properly installed. I simply don't know.

Tear it down. Clean it up. Check the fit of the differential (spider gear cases) housings on the axles. Parts for a standard differential are dirt cheap. I have piles of them from rear ends torn down looking for useable axles and bearings for Ruckstell rebuilds. Axle gears don't wear nearly as much as the cases do. Check the wear inside the case where the thrust surface of the axle fits. Replace the case if it is much worn. If you need one I can send you one. Replace the thrust washer between the inner case and the outer housings with bronze or NOS babbitt. Don't reuse old babbitt thrust washers. Fit the thrust side first and them machine the off side one to fit. The little fibre washer between the axles costs less than a buck apiece. I make my own out of teflon. You can use the commericial ones and it will work just fine. Put one in, if there is a little slack sand another one down to fit. A little tight is OK and a few thousanths slack is OK.

IMHO the needle bearing ones are a waste of money and are not designed to take the abuse they get in that application.

I would not go to the work of pulling the rear end and splitting the cases and then not tear it the rest of the way down to check the axle gears, the pinion gears and shafts and the clearances. It's not another hour's work.

If you are going to replace the ring and pinion -- I've been buying them from Ken Meek at Townsend Automotive in St. Clair Missouri. Fifty to a hundred bucks cheaper than the other vendors.

I should clarify this a little. Check the fit of the spider gear case housings on the axle GEARS, not the axles. What I am talking about is the fit of the case that holds the spider gears and how it fits on the axle gears. If you look it over you can see that the mesh of the ring gear and pinion, the clearances, etc., are all controlled by the fit of the case halves on the bearing surface of the axle gear. That is a critical fit. A good and pretty cheap fix is to take your cases to a good machinist if you don't have a lathe yourself and have bronze bushings pressed in and machined to fit the gears with about .002 clearance. It is very simple to do and very cheap. The only time the axle gears turn in the cases, theoretically, is when one wheel is rotating faster than the other, such as in a turn. In reality, they are probably rotating a little all the time because of differences in tire size, etc. In the past, who is to say what tires were run, how much plowing through mud and snow, etc., the differential did, and how much it was run with either bad or no lubricant. The bronze bushing is not so much so the axles can turn and not wear it again, it is just an easy way to bring the sizes back into spec. It is probably less than a fifty bucker at most machine shops.

I'd post some pics of what I'm talking about but after months of computer problems yesterday I had to go buy a new puter. Now I have to take it back because I bought too much memory and it is running 64 bit technology. I have to ask it to load 32 bit technology so I can get on the Internet but after getting on cannot post pictures or watch a youtube video, etc., because Adobe Flash player is not supported for 64 bit technology. I spent a couple hours last night trying to figure it out and this morning went to the computer repair shop and asked him about it. He said HP is selling this stuff and loading it with VISTA which Bresnan can't support for my ISP. He recommended just taking it back and getting my money back and getting one that is loaded with XP. Also, to get Office on this one, it is a $129.99 charge--that includes Publisher and Word since Microsoft's free downloads won't work with Vista for the older Publisher programs. This is a way for them to get 130 bucks out of every person who purchases a new computer. It's going back Monday.

Just a heads up. My son Johnny works as a techie at AMI communications. They have and are testing Windows 7 beta. Johnny says so far it looks like a real winner and not far from release so I plan to skip VISTA altogether and go from XP to Windows 7. Can't say for sure about that yet since W7 beta just hit town here but thought I would pass that along to those who might be on the verge of jumping into Vista which has not had a good run at all.

Keep away from Vista - my humble opinion (stuck with it, and also use Macintosh and XP).
Cheers
(and sorry to continue the thread hi-jack)
Adrian

Don't hold your breath. Micro$oft plans to milk Vista for little longer. W7 isn't due out until 2010.

To keep the topic on track: Yeah, what they said.

absolutely do not use the solid roller type bearings if you are replacing them. 2 of our club members, (myself and bud) had these in our rear ends (I put the one on mine 5 years ago, bud was unaware his was in there). Both of ours failed, mine during a tour which put it on the vulture wagon early, and his was a catostrophic failure that ended up with hospitalizations and a totaled car. Either use Fun Projects modern pinion or find a good original.

..and to continue the hijack, hopefully SP2 for Vista will make it run more like Windows7, which is SWEET!..

Make sure the new thrust washers are bronze and not brass. I saw a brass set that failed with very few miles on them. Also it is a good idea to put a small radius in the edges of the oil grooves after machining the plates to the correct thickness. This will let the oil get out of the groove and up onto the thrust face of the washer.
Art

Art - so there are brass thrust washers out there too?
Bronze can vary some in appearence, just as well as brass - but I suppose the bronze ones have a more reddish color, while the brass ones looks more yellow?
If someone has pictures of the different types, I'd like to see.

Then, to the roller type.. Earlier I hadn't heard about more than Terry Horlick's rear axle failure with this type of thrust bearing. Now there are several more, involving personal injuries. The vendors should plainly stop selling crap to us! (or at least write a warning like with the crap ersatz hyatt bearings)

I think the hardened washers used as part of the roller type thrust bearings have slots cut from the side for the retaining pins. This cutting may induce a risk of failure? (That's what I remember from the discussion years ago after TH's destoyed diffrential)

Thanks for the feedback. I'll tear it the rest of the way down and have a look see and replace the fiber washer between the axles.

I'll go back with the original setup. Snyders thrust washers are brass. I'll either make my own or find some bronze ones.

Doogie,

Are you talking about fun projects 2587E1 (non adjustable) pinion setup? Is this what others recommend?

I think some of you are confusing the solid roller Hyatt bearing replacements with the roller type thrust washers. I wouldn't use either one.

That's what happens when we start talking about everything but what the guy originally asked!