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View Full Version : How bad is NVH with Group N mounts? (other options?)



wcw2
11-04-2006, 03:54 PM
I've got a '98 Legacy L (2.2, 5spd) with about 135k on it. I'm doing some work on it over the Christmas holiday (clutch, rear main seal) and I think I could use some new engine and tranny mounts too. The Group N mounts are, oddly enough, a lot cheaper than the Legacy mounts. I'm looking to keep costs low on this, and the idea of slightly stiffer handling sounds good. But 95% of my driving involves getting on the highway and setting the cruise for 65mph. NVH (mostly noise and vibration-I can live with harshness) are big issues for me. How bad are these with the Group N mounts in a Legacy?

I absolutely can't take vibrations that will carry into the steering wheel, but I've heard that most of the vibration comes through the shifter stick, and mine vibrates already, so no big deal there. Noise is another subjective thing- I've got winter tires on and the engine is already at 3000 RPM when cruising, so I'm not sure how much worse a different engine mount could make things. Basically, I want to be talked into Group N mounts, or told if there's another option out there that maybe isn't as stiff, but costs a lot less than the $85/per cushion Legacy mounts cost online. Or, as a bigger question, do I even need new mounts? The engine moves less than inch side-to-side when I tweak the throttle, and I can't see any forward movement at all. The only reason I think I need new mounts is because of how the car bucks if I let off the gas and start to coast/engine brake. It's only a problem on the highway when I'm going downhill and trying to keep a constant speed- every time I switch from brake to gas, the car jerks.

Wiscon_Mark
11-04-2006, 04:43 PM
When you're cruising, I doubt it makes any difference. The real difference is under load, when the Group N mounts don't flex, the stock ones will.

You can bend a stock mount with your hand, I've done it. Sad.

there, I talked you into it :lol:

ten80
11-05-2006, 02:27 AM
I have the exact same jerking problem in my impreza TS and have a set of Group N motor mounts waiting to be installed. I can let you know what difference they make.

SHOfast
11-05-2006, 12:58 PM
I have the sti mounts, I do not know if these are the same as the gN mounts. The only time vibrations come into the cabin is when the engine goes into low idle, most noticably when the car is still cold. Other than that the regular noises and vibrations from driving at speed take over.

Wiscon_Mark
11-05-2006, 01:01 PM
STi Group N would the proper term.

jmgtp
11-05-2006, 06:33 PM
I replaced my trans mount with an STI Group N mount.

Noise: definetly more 'gear' noise - but nothing annoying

Vibration: tiny bit more felt only in the stick, even that may be in my head

Harshness: no way, it made it less harsh I think. It really felt like it tightened up the drivetrain

smoke3006
11-06-2006, 07:29 AM
Do they help with shifting (manual)?
When I had a Focus I replaced the lower motor mount and because it stopped alot of the engine movement it allowed for much smoother/easier shifts.
Right now the shifts in my Legacy are sometimes hard, in particular the 2 to 3 shift is rough.

ten80
11-06-2006, 09:11 AM
I don't know about the motor mounts, but my hardened tranny mount did help with shifting, along with the front and rear shifter linkage bushings, hardened shifter pivot bushing, and short throw shifter. Reverse is still a b*tch, but not quite as difficult to engage.

wcw2
11-06-2006, 09:52 PM
Hmm, good to hear. I'll probably go ahead and put them in then. Anyone know who's got the best prices for engine+tranny(+dogbone?) package? Not much on ebay at the moment.

Wiscon_Mark
11-06-2006, 09:59 PM
www.subarugenuineparts.com (http://www.subarugenuineparts.com) has the best prices on tranny & pitch stop (dog bone) mounts...dunno who has the best on engine though.