how to: diff bushings
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
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From: sheppard AFB, TX
how to: diff bushings
alright. . . i got these urethane bushings from fdnewbie as a beta test. first of all. . . thanks ramy!!!! they installed great. . . 2nd, i cant drive the car due to some exhaust issues that happened during the installation.
it sucks. . . just make sure you dont do custom work BEFORE you make sure the engine and transmission and differential and ppf are in good straight lines. ;(
anyways, the construction is great. . . sorry, i didnt get any pictures of the bushings themselves. . . i thought i had. . . anyways, heres the deal:
first youll need to jack up the car. . . all i did was the rear. no real need for the rest of the car to be up in the air unless youre planning to do something else. . . as i will be doing. :/ take off the catback while youre doing this. . . after the cars jacked up.
then, take off all the covers in the rear. this will show the braces that need to be removed in order to get the job done.




it sucks. . . just make sure you dont do custom work BEFORE you make sure the engine and transmission and differential and ppf are in good straight lines. ;(anyways, the construction is great. . . sorry, i didnt get any pictures of the bushings themselves. . . i thought i had. . . anyways, heres the deal:
first youll need to jack up the car. . . all i did was the rear. no real need for the rest of the car to be up in the air unless youre planning to do something else. . . as i will be doing. :/ take off the catback while youre doing this. . . after the cars jacked up.

then, take off all the covers in the rear. this will show the braces that need to be removed in order to get the job done.
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
Likes: 2
From: sheppard AFB, TX
then, jack up the rear end. . . just support it. . . anyway will do fine.
once supported, loosen the bolts/nuts that hold the diff bushings to the subframe.





i found that going directly below the nuts/bolts was the best and easiest way. . . still tight. . . but the easiest none the less.
once supported, loosen the bolts/nuts that hold the diff bushings to the subframe.
i found that going directly below the nuts/bolts was the best and easiest way. . . still tight. . . but the easiest none the less.
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
Likes: 2
From: sheppard AFB, TX
after the diff bushing bolts are out, lower the differential until it rests on the rubber stoppers that are on the subframe or something. . . youll see them. 
now, its time to loosen the bushing bracket from the top side of the differential. i found it to be easier to do ALL of them from the passenger side. like so. . .



once you get all 4 nuts undone, take the bracket out through the passenger side. . . this is just about the ONLY side with any room. geh.

now, its time to loosen the bushing bracket from the top side of the differential. i found it to be easier to do ALL of them from the passenger side. like so. . .
once you get all 4 nuts undone, take the bracket out through the passenger side. . . this is just about the ONLY side with any room. geh.
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
Likes: 2
From: sheppard AFB, TX
and here you have the culprit. . . the clunk maker. . . the back breaker. . . bleh. . . the diff bushing bracket. 

notice the cracked action on my bushings. . .




notice the cracked action on my bushings. . .
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
Likes: 2
From: sheppard AFB, TX
now, just find someone with a press. . . that should be easy right???? hehe. . . garfinkle to the rescue. 


heres a picture of the nasty old turd. . .

and a comparo. . .


and a picture of what your wife will do once she catches on to the fact that youve spent so much time on your car!!!!!

alright, i hope that was a good enough write up. . . sorry if i missed anything. the installation is obviously the opposite of the removal and pretty much straight forward. i didnt think it was as hard as everyone else mentioned, but i could see how it could turn into a task.
once i get road worthy again, ill take the car out and let everyone know how they feel. one thing i noticed already is how STIFF the diff is. . . and should be!!! my other bushings allowed me to push on it with just my hands. . . moving it about 1/4 inches. yikes!!!
hahaha, anyways. . . i hope this helps some people out there. . .
paul

heres a picture of the nasty old turd. . .
and a comparo. . .
and a picture of what your wife will do once she catches on to the fact that youve spent so much time on your car!!!!!
alright, i hope that was a good enough write up. . . sorry if i missed anything. the installation is obviously the opposite of the removal and pretty much straight forward. i didnt think it was as hard as everyone else mentioned, but i could see how it could turn into a task.

once i get road worthy again, ill take the car out and let everyone know how they feel. one thing i noticed already is how STIFF the diff is. . . and should be!!! my other bushings allowed me to push on it with just my hands. . . moving it about 1/4 inches. yikes!!!
hahaha, anyways. . . i hope this helps some people out there. . .
paul
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yes it cleared up almost all the drive line slop. the car also did not pull to the side in the rear on hard launchs. they make a slight whine noise, but it sounds pleasant at times.
As an aside, you CAN get to those bolts that mount the bracket to the subframe through the suspension from the side. Pull the wheel and get a nice long extension. Also allows proper torqueing.
I went with the Mazdaspeed bushings... very nice. Shifting feels like moving a lever in a rock, really solid. Good mod, though the trailing arm bushings were better (REALLY feel that clutch engaging
)
I went with the Mazdaspeed bushings... very nice. Shifting feels like moving a lever in a rock, really solid. Good mod, though the trailing arm bushings were better (REALLY feel that clutch engaging
)
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
Likes: 2
From: sheppard AFB, TX
well, the bushings feel great. no more slop. everything feels nice and positive.
the FIRST thing i noticed was when i was backing out of the road that leads to my house. . . there was a definite "whine" sound. i assumed it was going to be a little more noisy. the loudest is while in reverse.
while going down the road, i no longer hear clunks or feel shimmies. the car feels a lot more solid now. there is a TINY bit of whine. kinda low pitched. . . but not too bad. if i had my radio on. . . i wouldnt notice it. OR if i still had tortoise launcher catback on there. . . i doubt id notice it.
i do understand that a major reason for this to be SUCH an upgrade for me is that my old bushings had already failed. i can say this however. . . stockers WILL fail. these. . . should last A LOT longer. . . theyre solid.
over all. . . i love em. no reason to take em out. i dont know what it feels like to have metal in there, but i can assume its not something i really care to deal with. this was nice. . .
BIG THANKS TO FDNEWBIE FOR LETTING ME TRY THESE OUT!!!!!
paul
the FIRST thing i noticed was when i was backing out of the road that leads to my house. . . there was a definite "whine" sound. i assumed it was going to be a little more noisy. the loudest is while in reverse.
while going down the road, i no longer hear clunks or feel shimmies. the car feels a lot more solid now. there is a TINY bit of whine. kinda low pitched. . . but not too bad. if i had my radio on. . . i wouldnt notice it. OR if i still had tortoise launcher catback on there. . . i doubt id notice it.
i do understand that a major reason for this to be SUCH an upgrade for me is that my old bushings had already failed. i can say this however. . . stockers WILL fail. these. . . should last A LOT longer. . . theyre solid.
over all. . . i love em. no reason to take em out. i dont know what it feels like to have metal in there, but i can assume its not something i really care to deal with. this was nice. . .
BIG THANKS TO FDNEWBIE FOR LETTING ME TRY THESE OUT!!!!!
paul
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
Likes: 2
From: sheppard AFB, TX
i havent had any issues like that. ill run it up a few more times just to make sure, but i havent felt ANY major vibration. . . just heard the noise. thats all.
these bushings can be squeezed, they arent hard like metal or even plastic. . . just harder than the stockers. i dont know what the durometer reading is for them, so. . . :/
these bushings can be squeezed, they arent hard like metal or even plastic. . . just harder than the stockers. i dont know what the durometer reading is for them, so. . . :/
Originally Posted by rotorbrain
over all. . . i love em. no reason to take em out.
I had ya going there for a sec, didn't I? 
NP Paul. I'm glad you like them, and I was confident you'd do an excellent and fair writeup about them. You proved me right
Thanks for the writeup and your impressions!And the reason they're not hard is cuz they're made from made of 90A polyurethane, which is the expensive high-grade material.
Originally Posted by TeamChin
I NEED a set...FDnewbie, want another test subject???
The grinder has tolerances of 1/1000th of an inch (.001), so it's very accurate. But I think +-.005 is good enough for bushings, which is why Paul got a set with .005 difference from each other.
~Ramy
Thread Starter
fart on a friends head!!!
Joined: Mar 2002
Posts: 4,104
Likes: 2
From: sheppard AFB, TX
Originally Posted by FDNewbie
Paul, whatcha smokin? Now that you've tried 'em out, take 'em out and give 'em back! :rofl
I had ya going there for a sec, didn't I? 
I had ya going there for a sec, didn't I? 

Originally Posted by FDNewbie
NP Paul. I'm glad you like them, and I was confident you'd do an excellent and fair writeup about them. You proved me right
Thanks for the writeup and your impressions!
Thanks for the writeup and your impressions!
Originally Posted by FDNewbie
And the reason they're not hard is cuz they're made from made of 90A polyurethane, which is the expensive high-grade material.

Originally Posted by FDNewbie
Thanks for the offer, but I already sent another set to Phil (Herblenny), which is one more set than I anticipated. One of the main reasons is these bushings are a huge PIA to make, since urethane is so hard to cut accurately. These CANNOT be machined. They must be done by hand using a grinder, so they're done one set at a time.
Originally Posted by FDNewbie
The grinder has tolerances of 1/1000th of an inch (.001), so it's very accurate. But I think +-.005 is good enough for bushings, which is why Paul got a set with .005 difference from each other.

seriously. . . i wouldnt have known if you hadnt said that just now. they both went in just as expected and felt like they had the same fit.
GOOD WORK. lets see some more!!!
paul
Nice Write up Paul!
I'm going to pull it out soon... maybe this weekend and install the bushings.
By the way, Bushings looked great and definitely quality work.
I will also take tons of detail pics. I'm currently trying to pull an engine from another car and put my new engine in. Phew!
I'm going to pull it out soon... maybe this weekend and install the bushings.
By the way, Bushings looked great and definitely quality work.
I will also take tons of detail pics. I'm currently trying to pull an engine from another car and put my new engine in. Phew!
To anybody in this thread who has recently replaced their bushings - I might be interested in buying your old ones -
https://www.rx7club.com/showthread.p...=1#post4747981
https://www.rx7club.com/showthread.p...=1#post4747981
Will these be offered at a lower cost than rx7.com diff bushings which is at $120/set?
I freaking hope not since I got a set sitting right here.
I'd be interested in other suspension bushings. Poly don't require as much maintenance, don't they?
I freaking hope not since I got a set sitting right here.
I'd be interested in other suspension bushings. Poly don't require as much maintenance, don't they?
The rx7.com bushings are plastic; these are urethane. We're working on making a few (very very few) complete sets, as the amount of manual labor required is simply making it not very worthwhile lol. We may have a small amount of material left to make one or two more sets of diff bushings only. Price is still TBA, depending on how long the material we have left lasts.
Thanks
~Ramy
Thanks
~Ramy




