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96SEChick
11-03-2002, 10:17 AM
Does anybody have any experience with the subframe bushings going bad on their cars? Since I bought my car, I've always had this "clunk" when shifting from 1st-2nd. I had my transmission mount replaced Aug '01, but it didn't fix the problem. This past week, I took my car back to the dealership to see what was wrong again (I only took it to the dealership because I have an extended warranty) and they told me I needed ANOTHER new tranny mount because my subframe bushings are going bad, but my warranty won't pay for the bushings to be replaced. The kicker is also the fact that you can't get just the bushings from Nissan--you have to get the whole subframe ($500). You can get Nismo subframe bushings ($120 for all 4), which I know is the best deal. But the dealership wants to charge for 6 hours of labor (at $68/hour---ouch!!).

My question is--what exactly is the subframe? What do the bushings exactly do? And lastly, what will happen if I don't get these replaced?

Thank you for your help--this is the first time I've been completely clueless about something on my car. I'm frustrated!

Replicant_S14
11-03-2002, 10:59 AM
In an over simplified nutshell, the sub-frame is what holds your rear suspension together and the bushings isolate it from the rest of the car.

It sounds like you're getting a little BS about it because I don't see why you can't just replace the bushings. My guess is that it's easier for them to just replace the whole subframe and if you asked them to just replace the bushings, it'll be just about as expensive. It is a lot of work.

The sub-frame bushings just don't last on these cars. It was kind of a goofy design to begin with and if you look at one you'll see what I mean.

I cut some 1/4" think, super hard urethane spacers to go on the top and bottom of my broken subframe bushings and it seems to be oK. I don't have the "clunk" anymore and the car handles at the track as good as it ever did. Some guys in my local club have made some spacers using washers (like from a hardware store) and they seem to like it. I think someone is doing a "write-up" about it. I don't think it was difficult so, if you feel like doing some minor wrench spinning , stay tuned and I'll send a link when they get it done.

I drove mine around for a long time with it clunking. I don't think you need to be in too big of a hurry about getting it sorted out.

96SEChick
11-03-2002, 11:42 AM
Wow, thank you for the info!  Well, I called around to another Nissan dealership parts dept in town and they said also that Nissan doesn't sell the bushings separate from the subframe itself.  And they want $500 for the parts, too.  

If one of your friends can do a write-up on how to "rig" it up with polyurethane washers, that would be awesome!!  Thank you so much!

Replicant_S14
11-03-2002, 12:01 PM
Well, the other guys used steel washers. I used urethane just because I had some in my shop and I thought that having some "give" between the S.F. and the body would be good but apparently, it isn't necessary. I will most likely replace my urethane spacers with the washers like they did.

Anyway, I'll see if I can light a fire under them and get you the info.

BadMoJo
11-03-2002, 12:46 PM
OR... you could get aluminum subframe spacers for like 65 bucks and it will take you like 30min max to install.

This will make the rear of the car feel alot more solid, but it will transfer a bit more road noise into the car. But to me it seems worth it.

Replicant_S14
11-03-2002, 01:48 PM
Yeah, the washer thing is sort of the ghetto version of that. It's dirt cheap but you do have to slot the top ones. The road noise theory would apply as well although most people don't even notice.

Where can you get the aluminum ones? Are there pictures anywhere?

adey
11-03-2002, 01:49 PM
Having gotten in on the Subframe group buy, I must say that they're a nice piece. They were easy to install, and stiffened up the rear end. There's less 'slop' or 'play' in the back under cornering than before. It did, however, cause more noise (road and differential) from the rear, too.

While these aren't really a fix for shredded/dead bushings, it will help somewhat. If you take a look in the GB section for a subframe spacer GB that was held a while back, the spacers can be had for somewhere around $80 shipped now from C Park (Charles Park, I think) -- he runs a legit business and is a good guy. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'>

96SEChick
11-03-2002, 04:30 PM
Wow, in the year and a half I've had my car, I've never seen as much info on this subject as I've read in this 1 day. &nbsp;Nobody has ever asked questions about subframe bushings! &nbsp;You guys are awesome! &nbsp;Thank you!

Does anybody know where I can find a write-up or diagrams, or anything to show what I need to do to fix this problem myself (other than taking it to the shop and spending buttloads of $$$<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'>? &nbsp;I don't even know what my subframe looks like (the stupid mechanic took it off the rack before I got there so he couldn't show me what he was talking about).

adey
11-03-2002, 08:29 PM
the rear subframe... it looks like a big rectangle (a trapazoid)with an "x" in it (if I remember correctly), and it's bolted down with 4 bolts, and other 2 little 'arms' that also bolt from the subframe to the frame.
If you order the subframe bushings from Powertrix, you'll have instructions that are pretty good. I can't imagine nismo polyurethane mounts not having instructions either, though.

It's hard to miss with your car on jackstands- take a look underneath and it should become obvious. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'>

camppain
11-03-2002, 08:54 PM
your nissan dealer is trying to fudge you over probably to avoid doing more warranty work on your car.

yes the rear /f bushings can be changed by themselves! we did it at my dealer when i worked there. its a pita and every tech hated it but you do not need a whole new subframe!

tell them you are gonna call nissan corparate and that you already consulted other nissan shops in regards to the matter and they said the bushings can be changed.

96SEChick
11-03-2002, 09:39 PM
They didn't tell me that they couldn't change just the bushings, they told me that Nissan doesn't sell the bushings by themselves--only w/ the whole subframe assembly. &nbsp;I did call another Nissan dealership in town (I have 3 in Tulsa/Broken Arrow area) and they said the same thing.

But I finally did find the post on the Subframe Spacer group buy from Aug&Sept and the spacers sounds like a good deal, but I have another question about them:

My bushings themselves are bad--how are the spacers going to help that fact? &nbsp;Will it stop my tranny clunk while shifting from 1st-2nd? &nbsp;Will this be an inexpensive temporary fix to the problem so I will still wind up still having to replace the bushings? &nbsp;Or will this take care of the problem completely? &nbsp;The bad bushings have worn-out a tranny mount in barely a year.

BTW--my favorite Nissan dealership out of the 3 has done all the work on my car so far (timing chain, 3 oil leaks, clutch master/slave cylinder, etc) and they aren't trying to avoid doing more warranty work on my car because they know that if it isn't covered under my warranty, I'm not getting the work done there. &nbsp;The warranty company paid the mechanic for 15 hours of work for the timing chain/water pump/belts job and it only took him like 8 hours. &nbsp;So, they're happy when my warranty company has to pay <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

Thanks for the help everyone!

adey
11-03-2002, 09:57 PM
All the spacers do is compress the original bushings. They may be softened or hardened or even torn/shredded (i doubt it), but what the spacers do is squeeze the originally ~3/4" thick piece of rubber into more like a >1/4" &nbsp;<1/2" thick piece. The spacer itself was a little less than 1" thick, if I remember correctly.

What the spacers effectively do is stiffen up the bushings, by compressing them. You could probably (even) just run the spacers w/ no bushings -- this would just make for an extra-harsh/stiff setup, with even more road and differential noise transferred to the cabin.

Let me make it clear though that you will probably hear new/more clunking noises from your car/the road with these spacers; you'll hear your differential clicking as well as road noise from tires. However, these spacers _are_ quality pieces that will increase performance and driving pleasure somewhat. (unless your idea of a "good drive" is a Lincoln Town car! )

oberkill
11-03-2002, 10:02 PM
Lauren,

Are you planning on doing this soon? I am doing a write up for my new webpage that is a step by step on completly rebuilding a S13. The first part is rebuilding the rear end including removing the rear subframe and replacing the bushings as well as adding subframe spacers. It will be a little differant for a S14 but close enough that you would be able to figure it out. I just need to finish the 97 KA into a 92 with Auto to 5 speed conversion and its writeup first. Shouldnt be longer than a few weeks. If you need to do it sooner I will write up a quick how-to with pics from my car. LMK!!

Alan
[email protected]

96SEChick
11-03-2002, 10:09 PM
Alan--I won't be able to do this by the time you get your work done. &nbsp;I have to replace my rear shocks first--they're both completely blown ( <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/crazy.gif" border="0" valign="absmiddle" alt=':crazy:'> ), and the bushings and/or spacers will be next. &nbsp;That would be totally awesome to see a write-up of how to replace the bushings.

I'm spending the next 2 months replacing the rear shocks, brakes all-around, and the bushings because I'm getting ready to sell my car <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sad.gif" border="0" valign="absmiddle" alt=':('> and I want it to be in 100% perfect mechanical condition. &nbsp;These are the ONLY 3 things wrong w/ my car. &nbsp;So, if the spacers themselves will be a fix for the next 83000 miles and the bushings won't affect anything, then I'll just do the spacers, since they compress the bushings like adey said.

Alan--just take your time and let me know when you get it done. &nbsp;I'm very curious to see what it takes for this job. &nbsp;Thank you all so much!!!

sykikchimp
11-04-2002, 08:02 AM
I don't think you could run just the subframe spacers.. &nbsp;and I don't think you want to run them on busted bushings.. &nbsp;The bushings themselves are actually about 2in thick, and are help inside a metal sleeve. &nbsp;When you put in the subframe spacer it compresses the bushing into the metal sleeve, effectively pre-loading the bushing. &nbsp;I think if your bushings are busted it may just push into the bushing, and not compress it, thus destroying it even more. &nbsp;If I was you I would go with new poly bushings. &nbsp;I think if you tear up the bushings by adding subframe spacers, you will get a good bit more clunk in the rear suspension becausethen nothing is helping control the subframe from shifting.

southside240
11-04-2002, 11:08 AM
This is how it was explained to me, i got em installed and have had no promlems....


&nbsp;
I figured I'd get a lot of questions, so here's the full explanation and
purpose of the washers. The OE rear subframe in secured to the rails and pan
of the car at 4 points. Each point is a hardened stud that extends out of
the frame rail, and the subframe is suspended from the studs and secured
with a nut and cup washer from underneath. There is a rubber bushing at
each point to insulate any resonance to the rest of the car. With this
design, the subframe "floats" under the car, not completely solid and spaced
away from the frame to allow for movement. Under a load, the entire subframe
will shift easily, giving the loose feeling in the rear end and allowing for
excessive wheel hop. In addition to the bushings, the space that allows for
give is about 1/4" at each point, so flex can be extreme under excessive
loads. Aftermarket bushings, like the Delrin units Stillen sells, only fix
half the problem, major companies in Japan offer subframe spacers that fix
the other half, these are custom machined spacers that fill the empty space
above and below the subframe. The combination of both is very expensive, and
the spacers, or "collars" as they're called, are hard to come by in the US.
This solution I have is both cheap and effective to eliminate the problem.
By using large steel washers, you can fill the spaces on top and bottom of
the subframe, filling in the gap and making the whole rear end more solid.
I cut a notch out of the washers on top to allow it to slide in without
completely dropping the subframe, supported by a jack you can lower it a
good inch without problems. I used two washers above and below to fill in
the gpas completely, the washers are secured by both the weight and force
of the car, and by the OE cup washers at the bottom, which hold them firmly
in place. The only way the washers can move is if the nuts themselves are
loosened enough to lower the subframe. Balanced Performance did this to
Chris's car as a temporary measure to help with traction, but they only put
washers on the lower side. Although it isn't the best way of doing this, it
is way cheaper than the alternatives and easier to do in most cases. The
washers are a special item, so you'll need to go to a large hardware supply
place to find them. They are cold-rolled steel, about 1/8" thick, and 3 1/2"
in diameter, with a 1 5/8" hole. Use your better judgement when looking for
something to use, obviously aluminum or something thin won't hold up very
well. take a look under your car and you'll see exactly what I'm talking
about. Again, this is not a PROVEN method, so there are no guarantees. It
does work in the same manner as the "collars" that are designed for it
however. I don't see how I've gone without it.

96SEChick
11-05-2002, 06:28 PM
Well, now I'm really mixed on what to do. &nbsp;Replace the bushings? &nbsp;Install spacers? &nbsp;Or both??

96SEChick
11-07-2002, 08:05 PM
Anybody have an opinion on this?? &nbsp;Should I just do the spacers, or should I have the bushings replaced? &nbsp;or both??

Thanks

Replicant_S14
11-07-2002, 08:44 PM
I'm sorry it got confusing. It seems like there are never any definative answers on message boards. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/lookaround.gif" border="0" valign="absmiddle" alt=':look:'>

If it helps, my bushings are shot like yours. I auto-x the car and do the occasional track event but it is primarily my daily driver. I'm going to do the washer thing that Nick (southside240) described because:

a: Nick lives 30mins from me so if I screw it up, I can call him.

b: I have tools and a garage and I like to do that sort of crap

c: I can't think of any disadvantage to doing it other than the possibility of slightly higher road noise which, I don't care about.

d: it'll cost about 5 bucks and take about 30mins.


The only other thing I can think of that might help you make a decision is to ask what class you run in scca? If you run in stock, you gotta' put the crappy stock bushings back in to be legal.(which is why I don't run stock)

240dude
11-07-2002, 08:47 PM
If your bushings arent completely shot (shouldnt be..my 89 werent and they are much older than your 95) then you should just do the spacers. great improvement. I just made my own custom spacers out of hard compound rubber and they work great. i would say you just need to get spacers seeing your car is on the newer side. Let me know if you have more questions.