View Poll Results: Which tranny mount do you prefer?
Stock rubber
![](https://ls1tech.com/forums/images/polls/bar2-l.gif)
![](https://ls1tech.com/forums/images/polls/bar2.gif)
![](https://ls1tech.com/forums/images/polls/bar2-r.gif)
![](https://ls1tech.com/forums/clear.gif)
38
43.18%
Energy Suspension
![](https://ls1tech.com/forums/images/polls/bar3-l.gif)
![](https://ls1tech.com/forums/images/polls/bar3.gif)
![](https://ls1tech.com/forums/images/polls/bar3-r.gif)
![](https://ls1tech.com/forums/clear.gif)
24
27.27%
Prothane
![](https://ls1tech.com/forums/images/polls/bar4-l.gif)
![](https://ls1tech.com/forums/images/polls/bar4.gif)
![](https://ls1tech.com/forums/images/polls/bar4-r.gif)
![](https://ls1tech.com/forums/clear.gif)
26
29.55%
Voters: 88. You may not vote on this poll
Transmission Mounts
#1
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I need a new tranny mount and I've been digging through the forums here for info to help me choose what kind to get, but information is relatively scarce and scattered all over. I want to get people's feedback on different kinds of mounts, especially anyone who has run more than one type. I am leaning towards a stock replacement but haven't ruled out the Energy Suspension mount. It sounds like the Prothane mounts are overkill. Two other issues I'd like to know more about:
1. Can using a poly tranny mount together with stock rubber engine mounts cause any kind of damage? One post claimed this could damage the bell housing.
2. Can any type of stiffer mounts actually trigger a false knock reading and cause timing retard? This seems far fetched to me but was also brought up by a few posters.
If anyone has any more good info they would like to share about tranny mounts feel free.
1. Can using a poly tranny mount together with stock rubber engine mounts cause any kind of damage? One post claimed this could damage the bell housing.
2. Can any type of stiffer mounts actually trigger a false knock reading and cause timing retard? This seems far fetched to me but was also brought up by a few posters.
If anyone has any more good info they would like to share about tranny mounts feel free.
#2
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Go with the Energy mount if you wish to replace your current mount with an aftermarket unit. They are relatively inexpensive and last longer than the stock units IMHO.
about the only time folks run into problems with heavy duty mounts like the Prothane or even solid mounts is when they are producing massive horsepwoer and are constantly leaving hard out of a dig. And also the harsh shifts some builders like to set up don't help either.
g
about the only time folks run into problems with heavy duty mounts like the Prothane or even solid mounts is when they are producing massive horsepwoer and are constantly leaving hard out of a dig. And also the harsh shifts some builders like to set up don't help either.
g
#3
TECH Fanatic
iTrader: (27)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
i put a prothane in my car and it definatly vibrates more. its funny that you mention false knock. my tuner said my car was retarding the timing i guess for some reason that we could not figure out. he said it kept resorting back to the low octane tables. i wonder if this mount has anything to do with it?
why do you recommend the energy mount? i was told that people were having problems with the energy mounts. i was thinking it has something to do with them being the wrong thickness or something.
why do you recommend the energy mount? i was told that people were having problems with the energy mounts. i was thinking it has something to do with them being the wrong thickness or something.
Trending Topics
#8
Launching!
iTrader: (35)
Join Date: Oct 2006
Location: Chandler, AZ
Posts: 288
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
What I learned from running low gear reductions, high horsepower and big tires on rockcrawlers... Match your motor and tranny mounts. If you're running a poly tranny mount, you should be running poly motor mounts... Same goes for stock rubber (which I prefer on the F-body). I've got 2 cracked TH350 housings sitting under my bench... ZERO cracked housings since I started matching mounts.
#9
TECH Fanatic
iTrader: (2)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
You always want the trans mount to give in a uni-body car due to the chassis twisting. Urethane motor mounts are fine, but keep the trans rubber. For example, if you are running solid motor mounts, you don't want to have a solid trans mount, you want a rubber mount so the chassis can twist around the powertrain. If you don't let it twist, it will twist the trans in two. I.E. broken bellhousing, broken extention housing. I think poly mounts could potentially do the same thing since they don't really give that much.
#11
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Good info guys, keep it coming. I have decided to stick with a rubber mount. The commonly available generic aftermarket one seems to be the Anchor 2817, Autozone has it for $15.99 with a lifetime warranty, seems like a good bet. Any parts store should have this or an equivalant.
#13
TECH Fanatic
iTrader: (9)
Join Date: Mar 2004
Location: Pasadena Texas
Posts: 1,318
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I've switched to Prothane after checking out how the Energy Susp. poly . part ripped in half. The mount didn't break like a stock one will,but still it was loose,and moving around. You should have no problems running a poly trans. mount with the stock motor mounts.
#14
TECH Apprentice
iTrader: (29)
Join Date: Feb 2005
Location: 906 (Sault Ste. Marie MI)
Posts: 349
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Well, $150 flatbed ride, $215 (I think, I managed to get a discount) later I put the stocker back in and no more vibration.
#19
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I put my new mount on today. I went with the Anchor 2817, standard rubber mount. I went by the writeup at Install University here. This was a little different than the instructions in my Haynes manual which do not suggest removing the crossmember but rather lifting the transmission until the mount can be lifted out. I like the I.U. way better, I found it easier to just remove the four bolts holding the crossmember on than to try to lift the transmission high enough to get the mount out with the crossmember still on the car. Plus removing the crossmember allows for easier access to the upper mount bolts. Two things I wanted to point out for anyone using the I.U. writeup:
1. The writeup says to place a jack under the transmission but not actually raise it, just have the jack there for support. I found that I did need to raise the transmission a little bit with the jack because the old mount had sagged over time (you can see this in the picture) so the crossmember could not be bolted back into place on both sides without first raising the transmission slightly.
2. The writeup says to tighten the tranny mount bolt to 77 lb/ft torque, but this proved to be way too much. This may be because a different mount was used for the writeup, since it also says the nut is 18mm but mine was 15 mm. I just put some locktite on the threads and tightened to about 40 lb/ft.
Below is a picture of the old mount and the new one side by side. You can see that the old mount has compressed over time under the weight of the transmission.
![](http://i158.photobucket.com/albums/t95/atd413/Trans%20mount/PB170473.jpg)
As you can see from the next picture, my old mount had been completely sheared off. When I removed it there was just a tiny bit of rubber still holding both halves together, which I tore off by hand since the old mount was stuck to the crossmember.
![](http://i158.photobucket.com/albums/t95/atd413/Trans%20mount/PB170474.jpg)
Thanks again to everyone who shared their experience and knowledge here, I feel like I may have avoided some costly potential problems by passing on the polyurethane mounts which I might have gone with otherwise.
1. The writeup says to place a jack under the transmission but not actually raise it, just have the jack there for support. I found that I did need to raise the transmission a little bit with the jack because the old mount had sagged over time (you can see this in the picture) so the crossmember could not be bolted back into place on both sides without first raising the transmission slightly.
2. The writeup says to tighten the tranny mount bolt to 77 lb/ft torque, but this proved to be way too much. This may be because a different mount was used for the writeup, since it also says the nut is 18mm but mine was 15 mm. I just put some locktite on the threads and tightened to about 40 lb/ft.
Below is a picture of the old mount and the new one side by side. You can see that the old mount has compressed over time under the weight of the transmission.
![](http://i158.photobucket.com/albums/t95/atd413/Trans%20mount/PB170473.jpg)
As you can see from the next picture, my old mount had been completely sheared off. When I removed it there was just a tiny bit of rubber still holding both halves together, which I tore off by hand since the old mount was stuck to the crossmember.
![](http://i158.photobucket.com/albums/t95/atd413/Trans%20mount/PB170474.jpg)
Thanks again to everyone who shared their experience and knowledge here, I feel like I may have avoided some costly potential problems by passing on the polyurethane mounts which I might have gone with otherwise.