About those special washers in the transmission mount

In the explosion picture below, washers 28 & 21 are called special. Does anyone have a picture?

Although it is not readily apparent, does #28 fit into #21?

I know the #27 sleeve goes into the spool so I would think that the #28 is also at the bottom of the poly/rubber spool and on the #21 special washer and that both stacked then go on the tongue shaped piece #18. True?

#28 is a flat washer with rounded edges and will end up inside the bore of #3 along with the sleeve #27.
Also remember that # 3 is fitted within the boss on the mount itself.
The diameter of #28 is slightly larger than the bore of #3 which may serve to hold the sleeve captive on mount removal.

Thanks for the info, really appreciated.

You don’t mention the special washer #21 and its relationship to #18 which I believe you are calling the mount. I’m on the search for these two washers, #28 & #21 or at least a picture so I can see how it all goes together. Obviously I found both washers are missing when I was having the tranny serviced and now I have all kinds of difficulties with #3 getting shredded during the test drive along with all kinds of noises getting transmitted into the chassis and cabin and lots of lip from the tranny shops. I have also been thrown out of 3 of them and told to find someone else. In a town of only 50K and the next shop being over an our away, things are getting a little desperate. I’m at the forth one now with all new poly parts on order.

IIRC, on the GM transmission, sleeve #27 goes below washer #28. On the earlier cars with the BW tranny, there were two sleeves #27, one above and one below washer #28, but on the GM400 mount the post itself has a shoulder on it that serves the purpose of the upper sleeve.

Drawing only shows one spring seat #4. I think some here will agree, just one is the way to go. There are some, though, who expect that two should be used, one at each end of the spring.

I completely removed the trans. mount and all the hardware from my car and changed things so I could use a full-size GM arrangement rubber ass’y. However, I kept everything I removed, and it is gathering dust out in the garage. You can have it all, if it will help, for postage. I can throw everything in a box and send it your way. Let me know.

As Kirbert said your mount post will have the upper sleeve built in. The remaining pieces are laid out in the pics. Order onto post will be flat washer 28, sleeve 27, stepped washer 21 and finally the safety tie 18.
This will put 28 trapped midway up the post. It is listed as a damper washer in parts listing. The stepped washer (21) is simply two washers of different ID spot welded together.
I can give you the parts dimensions if you need.

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Yes, we talked about this over a year ago, the picture is wrong? The washer that tightly fits inside bushing goes ABOVE the sleeve. Not sure why though. Does it keep bushing from moving too high?

Yes, my 1988 only had one seat on the bottom. Even a Jag Parts store thought I should have two, but I insisted only one. I know somebody here tried two seats - they couldn’t even get the final nut (#19) on the shaft.

side note: pay attention to #15. They are ‘spacers’. I thought they were washers first time, and put them on with #17 and #20. This made the plate, #18, slightly angled which didn’t allow bushing to move freely up and down. Once I learned my mistake and put #15 along with head of bolt (it’s quite hard getting them started in the little crevice), #18 was nice and flat and I was able to push bushing up and down with my finger.

Greg, the washer #28 is listed as damper washer. I assume the tight fit in the bore of bushing does in fact damp the movement of the post/gearbox rather than just have it bounce around on the support spring.

Does anyone know where to get these washers ???

For #28 you could use a flattened spring washer.
For #21 a combination of washers could produce the same shape and thickness.
I don’t think that exact dimensions ae critical on this application.

I went out to my garage and blew the dust off the hardware I saved after changing my tranny mount. I have everything shown in Baxtor’s photos, which I can send you if you are interested. (Including the tie-plate.)

Yes, please do so. Tell me how much, where to send payment and in what form. I will send and give you a mailing address.

Thanks, I really appreciate this.

You can use my personal email. ptipon@goldassets.biz

Package is on its way.

Just got home and there they are. Who do I write the check to?

I think I sent my name and address to your e-mail link. I just sent a PM to be sure!