Transmission Mount/Torque Arm Bushing

[JoeliusZ28]

i didnt feel any more/less vibrations when switching from my poly to the LS1 mount. only difference i noticed was the "up-and-down" motion of the shifter was a little more prevalent.

I actually switched to the LS1 mount to try and help my shifting problems, but i have since fixed that issue by other means (pistol grip). I dont know how much of a hurry you are in, but if you wanted to wait for me I would swap my poly mount back in and sell you my LS1 mount for next to nothing if you wanted to come pick it up. not sure how far you are from me. I could do it this weekend.

edit: on second thought im not sure if 6 speed and autos use the same mount. check on that if youre interested.

[archemedes]

poly will have more vibrations typically, it's stiffer than rubber. I usually advise if one mount is bad replace all of them, it's not exactly cheap, but it will make the car drive alot different, and don't forget your cradle bushings

[randall814]

don't GM trannies only have 1 mount? im pretty sure most GM transmissions can share mounts. when i was looking in jeg's and summit catalogs at work, they only showed mounts with generic "GM" or "Ford" and in some cases "Jeep" descriptions. that's about as specific as it was. when you search specifically for fbodies, it doesn't require you to specify whether its auto or standard and the descriptions doesn't differentiate between them either.

also, are you referring to the TA bushing as well as the cradle bushing when you say "all of them"? where can i find the cradle bushings on the car?

[jz5w63]

Had same thump on hard auto shift from first to second last week in my '96 LT1 TransAm 5.7L/4L60E. From previous posts suspected the trans. mount. Bought a "stock" mount from Advance Auto (same thing at NAPA and Autozone) branded as "Anchor" and is cheapo Korea product. Put it on just in time for Woodward Cruise and car ran fine. Switched steering wheel over to the wife (I drove the cruise last year - her turn this year) and she got siked up by the crowd - "revvv it up, burn-out" - and she did just that reving it and then dropping it into D. Guess what - same bump/thump in the tunnel just behind the front seats! Suspected the mount again and the next day jacked it up again and sure enough the new mount had separated completely from the bond point of the rubber to the metal! What a piece of light duty crap! Took it back to Advance and got my $ back. Ordered a Prothane 7-1604 from Summit (same thing from Jegs) and hope it fits. Checked rest of suspension and powertrain and all mounts look good and tight including the torque arm. Hope this new trans. support does the trick. Any other experience from anyone on this? I hear the polyurethane ones may be stiffer but on my auto may not be as big an issue as with 6 spd manual re shifter shake/vibration since I believe the linkage for auto is a cable. The original mount (might not be the original?) seemed a little heavier/thicker rubber than the Advance Auto unit. I can't believe the latter is being sold for a Camaro or Firebird but maybe because they fit most GM's they are okay for lighter duty applications because they sure don't handle the torque from the 5.7L. Pity the aftermarket auto shops don't stock the heavier duty or polyurethane mounts. Any other suggestions/comments out there?

[randall814]

Had same thump on hard auto shift from first to second last week in my '96 LT1 TransAm 5.7L/4L60E. From previous posts suspected the trans. mount. Bought a "stock" mount from Advance Auto (same thing at NAPA and Autozone) branded as "Anchor" and is cheapo Korea product. Put it on just in time for Woodward Cruise and car ran fine. Switched steering wheel over to the wife (I drove the cruise last year - her turn this year) and she got siked up by the crowd - "revvv it up, burn-out" - and she did just that reving it and then dropping it into D. Guess what - same bump/thump in the tunnel just behind the front seats! Suspected the mount again and the next day jacked it up again and sure enough the new mount had separated completely from the bond point of the rubber to the metal! What a piece of light duty crap! Took it back to Advance and got my $ back. Ordered a Prothane 7-1604 from Summit (same thing from Jegs) and hope it fits. Checked rest of suspension and powertrain and all mounts look good and tight including the torque arm. Hope this new trans. support does the trick. Any other experience from anyone on this? I hear the polyurethane ones may be stiffer but on my auto may not be as big an issue as with 6 spd manual re shifter shake/vibration since I believe the linkage for auto is a cable. The original mount (might not be the original?) seemed a little heavier/thicker rubber than the Advance Auto unit. I can't believe the latter is being sold for a Camaro or Firebird but maybe because they fit most GM's they are okay for lighter duty applications because they sure don't handle the torque from the 5.7L. Pity the aftermarket auto shops don't stock the heavier duty or polyurethane mounts. Any other suggestions/comments out there?

It's been a while since I sold my T/A in 2008, but I replaced the transmission mount and torque arm bushing with poly units, and it definitely did transfer more vibrations into the cabin. It's worth it though...they were nearly bulletproof on my nearly stock car. Everything about the car shifting through the gears seemed so much tighter. This was on an A4, and prior to that, I never had an A4, so I have nothing to compare it to except the old mount. What's more is who knows how long that mount was torn before it actually gave out.

Long story short: get the poly mount and bushing.

[sman]

Had same thump on hard auto shift from first to second last week in my '96 LT1 TransAm 5.7L/4L60E. From previous posts suspected the trans. mount. Bought a "stock" mount from Advance Auto (same thing at NAPA and Autozone) branded as "Anchor" and is cheapo Korea product. Put it on just in time for Woodward Cruise and car ran fine. Switched steering wheel over to the wife (I drove the cruise last year - her turn this year) and she got siked up by the crowd - "revvv it up, burn-out" - and she did just that reving it and then dropping it into D. Guess what - same bump/thump in the tunnel just behind the front seats! Suspected the mount again and the next day jacked it up again and sure enough the new mount had separated completely from the bond point of the rubber to the metal! What a piece of light duty crap! Took it back to Advance and got my $ back. Ordered a Prothane 7-1604 from Summit (same thing from Jegs) and hope it fits. Checked rest of suspension and powertrain and all mounts look good and tight including the torque arm. Hope this new trans. support does the trick. Any other experience from anyone on this? I hear the polyurethane ones may be stiffer but on my auto may not be as big an issue as with 6 spd manual re shifter shake/vibration since I believe the linkage for auto is a cable. The original mount (might not be the original?) seemed a little heavier/thicker rubber than the Advance Auto unit. I can't believe the latter is being sold for a Camaro or Firebird but maybe because they fit most GM's they are okay for lighter duty applications because they sure don't handle the torque from the 5.7L. Pity the aftermarket auto shops don't stock the heavier duty or polyurethane mounts. Any other suggestions/comments out there?

Not good


P.S. Holy thread from the dead...

[jz5w63]

Okay, bought a Prothane from Summit, installed it and noticed an immediate difference in shifts (automatic trans.) which were crisper and with more bite under hard throttle. Tighter is a good word and yes there seems to be a bit more sound/vibration including from the exhaust which is supported off the right side fo the trans so |I guess that should be expected but all in all I'd say the whole thing is a plus so far. I'm still a little worried that I might damage the transmission tail because I didn't change T/A or engine mount bushings and am worried that the most stable part might be the trans. mount now although the T/A and engine mounts all check out as solid. We'll have to wait and see but so far...no problemma. Install part of this job was a piece of cake even though I did it via a couple of hydraulic jacks and jack stands while laying on my back. Best way is to take the whole lower support bracket off (6 bolts) after first removing the single nut on the single stud from the bottom of the trans. support and then slightlyjacking up pan of trans. with block of wood and bottle jack. Then you remove the two upper bolts of the trans support and then reverse the process. Don't tighten the single stud nut until you have the 6 bolts of the bracket tightened. All is well that ends well!