D7 4T series,

Going back a few years, driven plate roller bearing wallowed out an oval, drive links held it together for awhile, but let loose whil'st I was doing some light work in the yard. Think I ran it for a total of 15 hours, that fitting never saw grease way before I owned it, I can post the photos again, amazing, that pilot bushing on the shaft sure must be hard material.

After some procrastination, and even being slightly intimidated by trying to find those parts and rebuild the one I took out, I grabbed that complete one from the other forum. Out of a running tractor, did not slip, linings appear good in the photo, pilot bearing supposed to be good, but won't know until it gets here.


6B4672 & 6B4106 plate assemblies, anyone know what the thickness of the 8B7073 friction material segments is or approximate when new ? I know the one I took out, one plate was close to the rivet heads, the other was a little thicker, so if need be, now is the time, segments are available at Regal, any other sources for those friction segments? Only other thing I'm wondering about on this is, what kind of rivet gun and or rivets 6B4594 can be found to do the re-lining ? On the complete one I've got coming, I'd like to check the segments and decide whether to re-line them before installing it. I've heard Chicago rivet, mentioned before, still available ?


6B4076 Driven Plate Assembly: I plan on taking the front plate off the complete clutch assembly I bought, to get a look at and inspect the bearing, 1B3708 roller assembly, assuming it to be in good condition, but if not, looks like you have to shear off that collar, and replace the seperate parts in there, there is like 7 or 8 as per the 3T parts book I am using for reference. Regal or what may be the best parts source to replace the innards on this driven plate if it needs it ? ALso, is there a specific type of grease for this bearing, thought there was, don't want to do this a 2nd time and will be darned sure to grease that bearing, can't believe what I found, one part shiny the other rusted and or seized, cannot believe it held together for so long. I'd also be leary of using substandard parts, so that bearing, maybe cross references to a reputable manufacturer or something if Regal is not recommended, do not want to go in there again if I can help it.

6B4075 retainer, 6B4076 seal, 6B4077 gasket, 6B4074 retainer, 1B3708 roller assem.,1B3079 race, 7B7935 rivet, appear to be the driven plate (innards) parts numbers from this old 3T parts catalog up to 3T19999. I have just about every manual for this 4T,military technical manuals etc., but use the 3T parts catalog, looks like the same assembly, also this is the earlier dry clutch release mechanism.


Either this good used one will be a plug and play or I will need to reline the plates, put a new bearing in the driven plate and replace the bushing sleeve 6B4117, appears simple enough, but am looking to hear from anyone who has done this before and what the best sources of parts are.

Am aware of having to check radial and axial dimensions as called for in the book, from the engine flywheel, the engine has never been out, so I 'm thinking it is probably good, but best to check while I am there. Also made note of the washers-spacers where the drive links are stacked and pinned, will use the arrangement as found on the clutch assembly I took out.

I could not figure out why this thing vibrated so much, the fenders were a flappin, before it came apart, and boy are there some bolts missing there, anything else to worry about stemming from a driven plate being ovalled out of round causing heavy vibration ? Floor plates used to come loose, but I'll bet it will be night and day once the new one is installed.

Other than that, seems like once I am comfortable that the clutch assembly is in good shape as is or need to do the above, should be able to drop er in and be done with it.

Also, last few times I fired er up, the pinion was kicking out too early, have the earlier type on this I believe, and am aware of the adjusting process, but noticed that 6B1909 spring is missing, ( think I found it in the lower bell housing) and the screw 3B5121, cotter pin 3B4610 appears missing, not sure what happened in there but looks like while the upper bell housing is off, only way to get to this pinion ? Looks like it is, best source for these parts ? Have not even pestered the local Cat dealer, last time I was in was '01, friendly and helpful, not sure what the best source for parts as listed in this post. Not sure what else to be aware of on this pinion, but after replacing those parts, should be good to go I would think.


Well anyway, do highly appreciate any tips on replacing a dry type clutch, and will probably have more fun questions as I try and get this thing to get up under it's own power, service, lube and do as much as possible to get it in decent running shape. Never planned on workin it heavily, but have some free crushed stone coming in when the power company takes up the temp road base and restores the area, they put down over 1000 ton, so it would be great to get er running for this and get some rust off the tracks.

Hi Billy D7 4T,
just back from touring South Oz. This data is from my D7 Serviceman's Reference Book form No 7196G dated 8-46 page 164. Hope this helps,
Cheers Eddie B.

I have some d7 use parts for cluch and startor pinion

I went way overboard posting here on this, lately I tend to overthink things too much, and or absorb too much information, hence the detailed inquisition on a dry clutch.

I pulled the clutch out in '05 and had not been able to get back to it. I just bought a good used complete assembly, that could probably be dropped in as is. It would be nice to know what the thickness of the friction materials should be when new for both the main clutch plates and the clutch brake, to compare. Rationale is, while it's out, might be best to do it now, as with the use it gets, probably last a long time.

I did some research on replacing the friction segments, and see what is involved there, drilling the holes with counter bores, sizing the rivets ( assume they can be had from Cat, or elsewhere etc.) using the hand tools to clinch the rivets using an anvil underneath, good rainy day job. Pilot bearing and sleeve on the shaft, looks straight forward to replace, except getting the sleeve/bushing off the splined shaft, looks like a puller is needed, so you can get that off and get the other plate off to replace the friction segments.

I also had a look at the pinion on the spare pony transmission, it's intact, looks like when my clutch went out, it may have bumped the pinion, knocked the spring out and the screw cotter pins, just have to figure out how to replace that spring, and keep the setting it was at, so it releases properly, not too soon or to late etc.

With all the research and taking a look at things, I think helped me get past the mental block I was having for no reason LOL, darned thing aint that complicated, and with a complete assembly to look at, kind of cleared things up quickly.

Hector, thanks, I may contact you regarding parts, your a few hundred miles to the north, have not been in your neigborhood since march '04.

Eddie, thanks for posting that, saw that in the book too and finally understand what is involved on those segments.

Won't be long now, weather just turned nice, time to get at it.

Hi Billy,
What you have there is a "classic" case of the longer ya think about it, the bigger the job gets:) Just need to get in there and do it........not that big a challenge. Clutch specifications seem hard to come by or are non existent. Many folks have asked for thicknesses of clutch plates and discs but I have not seen any such specifications for the old stuff. Seems to be strictly eyeball judgement of condition, rivet heights, wear patterns and general wear. Back then I don't think there was much of a market for resurfacing plates either. Even when it comes to replacement parts now you are probably confined to good used so there aren't a lot of options. Just get-r-done and I'm sure answers can be had to specific questions.

O.M. you are right about that, less thinking, more doing ! This seems to happen more now than when I was younger. I had wondered what the thickness was for comparison to what is on there now, the original clutch assembly that was taken out, the front plate was just getting to the rivets and the segments were starting to get flimsy, no doubt it would not have lasted much longer. I'll measure up and see what I have, then ask, as I have no idea as to the rate of wear on these is.