Transmission Mount Replacement
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
Transmission Mount Replacement
I have a bunch of small jobs on the go right now. One of those is to replace my 4-speed transmission mount in my 70. I jacked the trans a touch off the mount and unbolted the mount from the trans and the frame, but I can't get it out due to the bracket / hanger on top of the mount...which I believe to be the center hanger for the exhaust? Any advice on how to get the mount swapped without a bunch of disassembly? Especially reluctant to start messing with my exhaust, as I doubt it will take it well.
Thanks in advance.
Thanks in advance.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
The mount looks like a sandwich, top and bottom plates and rubber in the middle...between the bottom bracket it sits on and the trans is another bracket that curves down and that traps the mount in there...can undo the bolts and slide it back and forth but can't get it out. I thnk it is this:
http://www.parts123.com/parts123/yb....Z5Z5Z50000050G
http://www.parts123.com/parts123/yb....Z5Z5Z50000050G
Team Owner
Joined: Sep 2006
Posts: 31,289
Likes: 4,380
From: Westminster Maryland
Hi B,
I see what you mean about the rubber mount being trapped by the horse-collar.
The only way I can see to get the rubber mount out is to drop it straight down.
To do that you need to drop the Transmission Mounting Bracket (4 bolts and nuts). It's item #5 on the transmission mounting sheet in the AIM. In 71 it's UPC6 Sheet B4. You can see 2 of the bolts (vertical- near the rubber mount) and 2 of the nuts (horizontal near the exhaust clamps) in this picture.They're plated 'brite'.
I think once it's loosened you can tip it enough to get the rubber mount out.
Good Luck!
Regards,
Alan
I see what you mean about the rubber mount being trapped by the horse-collar.
The only way I can see to get the rubber mount out is to drop it straight down.
To do that you need to drop the Transmission Mounting Bracket (4 bolts and nuts). It's item #5 on the transmission mounting sheet in the AIM. In 71 it's UPC6 Sheet B4. You can see 2 of the bolts (vertical- near the rubber mount) and 2 of the nuts (horizontal near the exhaust clamps) in this picture.They're plated 'brite'.
I think once it's loosened you can tip it enough to get the rubber mount out.
Good Luck!
Regards,
Alan
Last edited by Alan 71; Apr 10, 2013 at 05:03 PM.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
Thanks Alan. I got as far as taking the two vertical bolts out the other night before I threw in the towel. I'll make sure to grab my AIM and look at pulling the two horizontal bolts tonight...I think that would work. Thank you.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
This job didn't go well for me...dropped the bracket down without much issue, but the new mount I had from CC was at least 1/4" taller than the one in there. I couldn't get everything to bolt back up with the new mount, so I put the old one back in (closer inspection revealed it wasn't that bad anyway, just filthy).
Anyway, trying to get the bolt holes to line up was a real challenge, and at some point I must have gotten one of the bracket to trans bolts in at a bit of an angle and I managed to strip the first 2 or 3 threads in the trans. I realized what was happening and stopped before it drove too far. Getting late here, so walked away for the night.
What is the best way for me to go with these threads? Tap?
Anyway, trying to get the bolt holes to line up was a real challenge, and at some point I must have gotten one of the bracket to trans bolts in at a bit of an angle and I managed to strip the first 2 or 3 threads in the trans. I realized what was happening and stopped before it drove too far. Getting late here, so walked away for the night.
What is the best way for me to go with these threads? Tap?
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Instructor
Joined: Mar 2013
Posts: 215
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From: Sunshine Coast Qld
The cheap way is to find a bolt of the same thread, and grind a groove down one side, kinda like a poor mans chaser tap. I've used this method a few times to clean up a thread that was damaged at the start. ymmv.
Safety Car
Joined: May 2008
Posts: 3,755
Likes: 721
From: Lafayette Louisiana
4sp transmission mount
I am swapping out mine on the 72 and just slide it out to the side, but my exhaust was all out. This was a "while I am in there" job which I am trying to put an end to those, ha!
Anyway, my old transmission mount is considerable shorter than the new one I ordered. I am guessing the rubber gets compressed over time. So, maybe your new one is like it is supposed to be?
Anyway, my old transmission mount is considerable shorter than the new one I ordered. I am guessing the rubber gets compressed over time. So, maybe your new one is like it is supposed to be?
Last edited by 20mercury; Apr 12, 2013 at 10:08 AM.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
Yes the exhaust holds the mount in there when the former is in place...did you manage to get the new mount in?
My big heartache right now is the transmission threads...ugh. Only 1/4" of thread in bad shape at most, but hard to know what to do. Consensus so far seems to be to try a tap to clean up the first couple of threads.
My big heartache right now is the transmission threads...ugh. Only 1/4" of thread in bad shape at most, but hard to know what to do. Consensus so far seems to be to try a tap to clean up the first couple of threads.
Last edited by Brcmpbl; Apr 12, 2013 at 12:41 PM.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
This job is done, thankfully. Used a tap to clean up the threads in the transmission...first time I've used one of those, amazingly effective. Also managed to get the new mount in, just had to raise the transmission ~1/4" to get everything to line up. Old mount must have been very worn. Thanks for the help with this one.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
Thanks guys. Have learned a pile in the past week. My friend had a nice tap set in his shop where I was working on the car, just had to look around a bit for it. Not much clearance in there so I used a pair of long nose vise grips, a little oil, and went super slowly and carefully. I was so happy when it worked.