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stsleeper94

Rear Differential Questions

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So I think my 1j is really making enemies with my rear-end and I am looking for ideas.

 

Car: 1989 Cressida, JZX90 auto, 4.30 Mkiii NA gears

 

As of right now the rear end makes a "chirp" sound whenever I shift out of P to any other gear. I put it up in the air and watched as a friend shifted it back and forth and it seems like something may just be wearing. I lack all knowledge when it comes to the ass end of my Cressida, so what can I do to make my rear-end stronger (all joking aside, yeah like that will happen).

 

Beech performance has some stuff for sale, but what is gonna get the chirping to go away and help me most, again don't know anything about this area of the car. Any help appreciated.

 

Thanks,

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Serialnine subframe bushings and diff bushings will make you fall in love with your car all over again.

 

http://serialnine.com/products/x8/chassis

 

 

 

also.. what is this chirping you are talking about? Is it the tire chirping? Is it an internal part chirping (like the transmission)?

 

Things that can go wrong in and around the diff are.. the crush washer on the pinion gear sucks on all cressidas. I believe this wearing out can lead to the backlash going out of spec and leading to other problems down the road (someone correct me if Im wrong). Another thing that wears out is the axels. I replaced both of mine last year because the U joint closest to the diff wore out on one and destroyed itself (this is something I only noticed when turning).

 

Without being there and hearing what you are talking about, these are just shots in the dark. Hope they help.

 

 

are you still open diff?

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I am on the mkiii LSD.

 

I think I am going to go home and take some video of the noise and post it so that you all can hear it and give feed back. I had it on a friends alignment rack, and he just put the front brakes on and shifted through the gears while a tech and I looked at it. Everything from the drive shaft forward looked and sounded good. It was the rear end when he would shift it that the noise, chrip (clunkish sound) would happen.

 

It is not coming from the transmission, that I know. The tech said he thought it might be the bushings, but didn't know for sure. I didn't hear something that sounded "internal" to any parts (Ie muffled noise). Seemed right in front of us. I could see the rear-end snap into drive and reverse and with it came the noise. Again will video tape tonight soon as I get home.

 

I feel and hear nothing while driving.

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Three things, google is your friend, learn about diffs because we shouldn't have to explain this shit to you, get a solid pinion spacer, not a new crush sleeve and DO NOT QUOTE ENTIRE POSTS ESPECIALLY THE POST DIRECTLY ABOVE! There's already a pretty good amount of info about diffs on here, read it.

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i see that mk4 in the garage more pics please :P

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OH shit lol mine is alot worse than that and i just went 1j o my x7. LOl first burnout = no more diff =)

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^lol yep, the wonders of the 7.5" diffs in X7s. at least he probably got a few days use out of his X8 before the diff got noisy.

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While we're OT, which pinion spacer kit do I need for my mkiii diff? The 4 or 6 cyl hilux kit?

 

I think this guys rear uni is farked, my old mans hilux used to make a horrible metallic clunk when you drop the clutch.

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I really can not even remember when it started making the noise. Its so hot in Florida with the A/C screaming and the windows up I only noticed it when I had to swap out the compressor on the A/C and drive without it for a few days. Regardless thanks for all the input. Going tonight after work to put it on the lift and remove pieces.

 

Also was directed to this site : http://www.weirperformance.com/solidpinionspacerkits.html

 

A few members recommend them.

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Turns out the issue is due mostly to play in the drivetrain. I guess me with a built auto makes a little bit more noise. I am going to have a custom driveshaft made (hopefully that will take out some noise/play going 1 piece to 2, try out the solid pinion, and serialnine bushings.

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My gold car developed the chirp noise and its just coming from the bushings them selves. Install the solid diff bushings and repair any cracks in the subframe. Cracks in the subframe would be caused from the diff rocking left and right slamming into the worn bushing sleeves. Also, your carrier bearing could be failing. 1 piece drive shaft is a good way to go.

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Thanks Mo, I was hoping to get a little feed back on the 1 piece driveshaft. There is a guy locally in Tampa that makes some pretty stout drive shafts for a very reasonable price. I have never really seen much discussion about the driftmotion steel or aluminum verisons, so do not know if that is a good route to go or just have it fabbed. For the price + shipping to this coast I think the local route might be the best fit for me.

 

Next time I get the car up in the air for the bushings install I will be sure to inspect the subframe and carrier bearing.

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If the shop has a good reputation, go for it. Another way you could test your diff bushings is if you leave your car in park, e brake released, get down and look at the two mounting points while somebody rocks your car back and forth. You will see the diff rock left and right and also hear the squeaks.

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Good info in this thread...

 

Getting some parts from weir to put a solid spacer in if anyone is interested on prices-

 

Pinion bearing set $133.40

Pinion seal $10.36

Solid spacer kit $39.00

 

Shipping to oz is $47, so thats $230 just for the luxury of a solid spacer lol.

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there not bad especially when i had the lsd rear in, with a welded diff its allot more noticeable (turning with weird popping etc...) my car is gutted so its kinda loud inside anyways.

 

I really dont think there is enough noise to even come close to off setting the advantages of the bushings. As long as your diff doesnt whine you prolly wont have any issues at all.

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Not much more noise and vibration, but acceleration is way snappier after that soft shit bushings is tossed out of the car. I'll be ordering some subframe solid bushings from s9 after I get my 1uz running. The car was just noticeably funner to drive with just the diff bushings, I'm really eager to find out how much more funner it could be whem everything else gets overhauled on the chassis.

 

Sometime before TORC next year, I'm hoping to get all my suspension bushings replaced.

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When is TORC Usually? Now that i actually live in the mainland.

And i got the bushings on my 7. Bumps on the road like the little reflector bumps seem to make alot more noise lol but noise in general isnt too much of a problem. But the handling improvement was crazy.

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TORC is in May. You got the subframe bushings? I could care less about noise since my car lost its luxo factor after I lowered it anyway.

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ya well for x7 the subframe bushings are basically subframe and diff.

Never even got to drive my car yet though after the swap. Got the JZ and it started up with problems and i had to leave for school the next day. My chick fixed the first problem but now i got some crazy 2-3k warm idle.

but haha christmas break im gonna go home and then send it up here.

But really the overall noise increase was so small, in all honesty if your worried about noise then might as well not even mod your car bro haha..

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