Is my TRANSMISSION MOUNT failing?.. SOLVED!!! NO MORE RATTLE

[d1giPhux]

Here is the issue on my 99 Subaru Legacy GT:

When i let off the gas, I can hear a clunking / groaning sound in the front of the car. Feels like the transmission is shaking around, and you can see the shift knob move around a bit. Its been progressively getting worse over time. The shaking / sound seem to come from the front of the center console area.. right near where the trans is.

It doesn't seem to do this when accelerating, its only when decelerating, or when letting off the gas abruptly without feathering it.

Seems to make a clunking / grinding / just all around NVH type sounds.

Can someone confirm that this is probably the transmission mount? Is there a way I can check easily without removing stuff? Anything else I can diagnose?

Also, I'm wondering: If the trans mount is failing, I am running a lightweight flywheel in the trans, which im SURE makes it move around a bit more, or differently than it should. Can i use an STI transmission mount in my car? Or what are the available replacements for the 5MT 99 Subaru Legacy GT? I looked at the STI mounts, and GROUP N, etc, but I think I just want to stick with something SLIGHTLY stiffer than stock, that way NVH wont go way up? What do people recommend?

Thanks!

[rougeben83]

go under the car and visually inspect the trans mount. Otherwise you can put a pry bar in the voids and see if there's excess play. You can go to Group N, I didn't notice a large diff but I already had Group N engine mounts and pitch mount so its all relative I guess.

I think I have a spare 5mt trans mount I don't need anymore, let me know if you want it.

[d1giPhux]

I think I want to go with something a bit stiffer since my trans has the lightweight flywheel on it, and engine has lightweight crank pulley. I think this is what caused it to wear out so fast. That and beating on it!

Do you think I can view the trans mount by putting the car up on ramps, or will I need more head room?

Hopefully its not too hard to install, I wonder if anyone has a DIY for the BD series vehicle? Or torque specs or anything?

I'm assuming its the trans mount going bad. Its the original one, and I can like FEEL the trans shaking around. Feels pretty bad..

Is there and STI mount that would work? Not sure if I want to go fully GROUP-N or not, and if there is an STI subaru one that would fit the 5mt, that would be awesome. Just not sure what my options are.

[Garrison]

Sti is 6 speed, and therefore does not mate up with the 5-speed bolt holes. They're clearly different if you go look at the Group-N site.

I advocate you take the option of grabbing a spare and making your own with 3M window weld. I did so, and it's still holding up beautifully 40k later.

[d1giPhux]

Yeah, i know that the STI's are 6spd.. but there APPEARS to be a 5mt version as well. Anyone know if this is true, or is this just a stock 5mt subaru mount??:

http://www.ebay.com/itm/SUBARU-STI-TRAN ... 97&vxp=mtr (http://www.ebay.com/itm/SUBARU-STI-TRANSMISSION-MOUNT-5-MT-IMPREZA-WRX-FORESTER-/130912915607?pt=Motors_Car_Truck_Parts_Accessories&hash=item1e7b049097&vxp=mtr)

And as much as id love to make one, I'm feeling lazy with modding my car now. I don't really care to mess with it anymore as its become more of a beater than ever in the past. I just wanna get it done and over with. :smt015

[rougeben83]

Just get the group N 5mt mount. The sti version is probably harder to get since the gc 5mt sti's were not sold in the US. Group N 5mt is easier to get ironically because wrxs are used in rally america and the like. You can see the trans mount while the car is jacked up. Its right under the middle of the trans.

[d1giPhux]

Gotcha. I'm just wondering if the mount will break in or not, or if I should go with stock, because I don't want any extra buzzing, or crazy downshifting sounds. Car is loud enough as is.

[decke48]

i put a group n on the forester, didnt really notice any real noise difference. all it did was tighten up the tran, and shifting, but this comes from the POS stock mount that was at 290k that you could move the trans with no effort every which way.

[d1giPhux]

Awesome. Good to know! Thanks man. Where is the best place to pick up one of these mounts from? Also, are they hard to install? I don't have a tranny jack or anything special like that.

Does anyone know of a DIY that is close to the way the BD series is done? Anyone know torque specs or where i can find them in FSM?

Thanks.

[Wiscon_Mark]

FWIW, I noticed no increase in NVH from the GroupN tranny mount. If you're getting that done, definitely do shift stay bushings at the same time. I did get a lot more noise from the pitch stop, but that was mainly because of a bad throwout bearing and mounting location being close to the clutch.

[d1giPhux]

Have any more info about the shift stay bushings? Not sure I even know what they are..

[Wiscon_Mark]

They're these:

http://www2.kartboy.com/x4/product.php? ... 263&page=1 (http://www2.kartboy.com/x4/product.php?productid=16139&cat=263&page=1)

They replace the bushings that hold the shifter stay to the transmission & body of the car. The ball joint of your shifter sits in the shifter stay, so stiffening that up will make your shifting feel a lot more crisp. It's not the easiest mod to do with the transmission still in the car (it's possible, I've done it 3 times) so if you'd be replacing the mount, I'd do it then.

Also, see Garrison's mod:
viewtopic.php?f=39&t=22968 (http://www.sl-i.net/FORUM/viewtopic.php?f=39&t=22968)

[d1giPhux]

Seeing as how I'll probably be doing this myself and I don't want to pull the trans.. no way, no how! I just want to get this done as easily and as quickly as possible since I will be working alone. How hard is it to install those kartboy rubbers you were talking about mark? Do you have any install info / DIY's anywhere? I'm pretty unfamiliar with removing any mounts / rubber parts in this area.

My shifter bushings I think are okay, as I don't really feel any slop. I'm not even sure my trans mounts are worn, but they must be since I can feel so much feedback from the transmission when downshifting!

[Huffer]

Check your pitch mount. If you're getting vibration on decel, then it's likely that your pitch mount is going - rev the engine by hand and watch it move - if it does, then it could be your pitch.

Course, it could also be a loose bolt on a mount.

[d1giPhux]

Hmm, okay. I will need to check out the pitch mount as well. It mostly happens when I let off the gas. As soon as I let off, if I let off suddenly it will kick and vibrate and I can feel it quite bad. Also happens quite a bit on deceleration..

[Wiscon_Mark]

GroupN engine mounts & the pitch stop are generally held as the cure to fix that issue.

The hardened shifter stay bushings aren't to cure slop (that's the shifter pivot bushing which is a different part), but they hold the pivot ball at the bottom of the shifter in place more firmly which means gear engagement feels more positive. I bought the Cobb bushings on sale and put them in my Forester and I noticed an immediate difference.

Even if you're not dropping the trans, you'll still be right in there, it's a good time to do it.

[d1giPhux]

Know any good shops that carry the group-N stuff that I can buy from with decent prices?

I'm going to check out all my mounts this weekend and see whats going on. I know some of them must be getting worn, as they are the original ones. I don't know if I will do any motor mounts or anything, as I have no engine lift. The trans mount and pitch stop mount I could probably do without an engine hoist.. I'm not sure, as i've never looked into doing this before. :smt017

[Huffer]

You don't have to go group N. You can always just by factory OEM replacements - they'll be brand new so they'll be in better shape than what you have most likely.

[d1giPhux]

I think I will end up going with the group-N, as I think the lightweight flywheel / crank pulley have added to the movement in the engine / trans and may have worn mine out prematurely. Then again, the car has tons of miles on it, and the mounts are original, so its probably their time anyways!! :lol:

[Wiscon_Mark]

You could also do a stock mount and do the mod Garrison did (http://www.sl-i.net/FORUM/viewtopic.php?f=39&t=22968)

If you find some cheap, low mileage mounts, this is a good mod.

[Regardie]

What is the proper part for Group N engine and tranny mounts on a BE? Never anything listed so I imagine it is an off book use.

-- Sent from my TouchPad using Communities

[Huffer]

What is the proper part for Group N engine and tranny mounts on a BE? Never anything listed so I imagine it is an off book use.

-- Sent from my TouchPad using Communities

Same as the GC Impreza, or the GD WRX. Basically anything up till 2005.

[d1giPhux]

So.. after finally getting around to solving this issues, it turned out to be simple and FREE:

The TRANSMISSION CROSSMEMBER BOLT was loose!!.

Turn out the bolt on the right hand side of the trans area crossmember was so loose I could turn it with 2 fingers!.

When i tightened both sides, the car drives and feels like NEW! No more rattles, no more groaning and grinding. Its completely quiet now, and the shifting feels GREAT!

This is AWESOME. SO STOKED!! :smt020

On a side note, the transmission mounts look fine, as well as the engine mounts. Which is great news! :smt023

[harrymaneuvers]

Love it when things like this happen!

Glad you got it fixed.

[d1giPhux]

Yeah, me too. It was starting to make the whole car feel ghetto.

Feels nice and solid now!

Cant believe just 1 bolt could do such a thing. Awesome it was a free fix. Makes me wonder if they should be 'blue-loctited'.