Do they make a trans mount in between factory and poly?
06-05-2015, 09:54 AM
#1
Do they make a trans mount in between factory and poly? So I currently have my factory original trans mount bushing and the shifter moves more than I'd like. I have poly engine mounts, so when I put in the poly trans mount, the vibration was just too much.
I'm sure my factory mount isn't what it was when new, but before I drop $100 on a new one, is there anything else out there as a replacement that isn't a poly bushing? Did they make a 1LE version?
I'm sure my factory mount isn't what it was when new, but before I drop $100 on a new one, is there anything else out there as a replacement that isn't a poly bushing? Did they make a 1LE version?
06-05-2015, 07:48 PM
#2
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06-07-2015, 09:42 PM
#5
If you're getting a driveline vibration, then shimming anything is just band-aiding the problem: incorrect pinion angle. If you're talking about general vibration from a hard poly bushing, then stock is probably your best bet. Ive got poly and I don't particularly like it but I live with it because I never have to worry about it breaking.
06-10-2015, 08:13 PM
#6
How is it a band aid if it fixes the problem? The poly mount is taller and makes the back of the trans sit higher and makes the pinion angle higher. Shimming the crossmember will bring it more in line with the pinion. Of course there will be additional noise and vibration that can be felt....its a stiffer mount made of polyurethane. Stock mounts may be quieter but are pretty sloppy. I dont like the feeling of my shifter jumping around. A poly mount was my first upgrade 12 years ago. That same mount is still in there with the same shims......20,000 street miles and 500+ passes and not a single problem.
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06-11-2015, 07:40 PM
#8
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I have also done the poly with spacers method described above but found the rubber washer trick resulted in smoother feel overall
I used digital angle finder for both methods
06-11-2015, 08:51 PM
#9
What worked for me was to get some rubber washers from lowes that are about the size of the stock trans mount. Dropped crossmember, added 3/16" of rubber washers, reinstalled crossmember.
I have also done the poly with spacers method described above but found the rubber washer trick resulted in smoother feel overall
I used digital angle finder for both methods
I have also done the poly with spacers method described above but found the rubber washer trick resulted in smoother feel overall
I used digital angle finder for both methods
06-11-2015, 09:00 PM
#10
I measured the height and was 3/8 difference. Solution... 3/8" spacer. And as far as pinion angle....what do you consider correct? I have measured several 4th gen fbodies that were completely stock and none had the same EXACT angle. I know i run mine at a angle that isn't the best for high speed cruising and i get more vibration.....but it works better for the drag strip.
06-11-2015, 10:07 PM
#12
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I measured the height and was 3/8 difference. Solution... 3/8" spacer. And as far as pinion angle....what do you consider correct? I have measured several 4th gen fbodies that were completely stock and none had the same EXACT angle. I know i run mine at a angle that isn't the best for high speed cruising and i get more vibration.....but it works better for the drag strip.
If trans angle is higher, then adding shims under the mount reduces the trans angle AND increases the rear pinion angle. Both relative to the earth.
If trans angle is lower, shimming between frame and cross member will increase trans angle AND decrease pinion angle.
Unless you're on the strip, making them equal is usually best. We both did the same thing - adjusted our cars to suit our needs. Only difference was the starting points and end goals.
06-12-2015, 10:51 AM
#13
You're right they are all different. I was trying to get the trans output shaft angle equal to the pinion angle.
If trans angle is higher, then adding shims under the mount reduces the trans angle AND increases the rear pinion angle. Both relative to the earth.
If trans angle is lower, shimming between frame and cross member will increase trans angle AND decrease pinion angle.
Unless you're on the strip, making them equal is usually best. We both did the same thing - adjusted our cars to suit our needs. Only difference was the starting points and end goals.
If trans angle is higher, then adding shims under the mount reduces the trans angle AND increases the rear pinion angle. Both relative to the earth.
If trans angle is lower, shimming between frame and cross member will increase trans angle AND decrease pinion angle.
Unless you're on the strip, making them equal is usually best. We both did the same thing - adjusted our cars to suit our needs. Only difference was the starting points and end goals.
There are people running all different angles and if it works for their set up so be it.....
06-12-2015, 04:37 PM
#14
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So I currently have my factory original trans mount bushing and the shifter moves more than I'd like. I have poly engine mounts, so when I put in the poly trans mount, the vibration was just too much.
I'm sure my factory mount isn't what it was when new, but before I drop $100 on a new one, is there anything else out there as a replacement that isn't a poly bushing? Did they make a 1LE version?
I'm sure my factory mount isn't what it was when new, but before I drop $100 on a new one, is there anything else out there as a replacement that isn't a poly bushing? Did they make a 1LE version?
06-12-2015, 05:17 PM
#15
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^^^This was a question I asked a while ago, but nobody had an answer (i.e.; do poly MOTOR mounts help 'save' the stock rubber trans mount due to less; torque twisting, and stress transfer, than stock rubber motor mounts??)
06-12-2015, 05:22 PM
#16
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I bolted my engine in solid 15 years ago when I had the Rover V8, and when I fitted the LS1 about 13 years ago, bolting it solid was just the easiest thing to do.
When clearance is tight, solid ensures it wont move !
I did buy a poly mount for the T56 at one point, but no idea how the **** they were selling it for a T56, because it was nowhere near a replacement for the rubber one, so I just left the rubber in place.
But yes I can imagine that the less movement the engine has, the easier things will be on the trans mount.
I would not bolt the trans in solid though, chassis twist will result in something breaking.
06-12-2015, 05:23 PM
#17
I have never had a problem with my rubber mount after I replaced it. Rock auto has an oem style one for 45 bucks btw, good quality as well. I had an energy suspension one and hated it, my buddy runs the prothane which tends to be a little softer than an energy suspension one and his isnt bad so you may want to look into that.
06-12-2015, 11:04 PM
#18
For the record, I do have poly motor mounts, which help, I just think the factory, 15 year old rubber mount is done. I'll try mounting the poly mount this weekend with proper spacers, if that doesn't make me happy, I look into getting a new factory one from Rock Auto.
06-13-2015, 06:09 AM
#19
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I don't know about saving the mount, but I do know a ton of guys, including me, run this config
06-13-2015, 09:27 AM
#20
Even after shimming my ES one still sucked but my buddies prothane went right iin and is pretty nice after break in. I'd still prefer stock though. I got a new oem rubber one 4 years ago from rock auto and it still looks perfect as of last week when i pulled the drivetrain. I have poly mm;s as well