maxitech

iTrader: (7)

My car has had an ISB in the transmission that has gradually been on its way out for the last two years or so. Wanting this car to be solid and reliable I bought a core VLSD transmission and took it to a local shop that specializes in Nissans to have this core transmission gone through with a fine-toothed comb and replace anything and everything that looked even close to worn so it would be good to go for many miles to come.

$750 later, I have (what I think) is a great transmission to put into the car. The unit was gone through and I was told everything looked good, but I had the ISB replaced just to be sure.

So I put this new transmission into the car over the weekend, only to be very disappointed.

For whatever reason, this unit (with a brand new ISB) is exhibiting the same noise with the clutch let out that the old unit with its worn ISB did, albeit not quite as bad.

How the h&ll does a brand new ISB sound like a worn out one!?!? Furthermore, the whine from first gear is MUCH more prevalent upon acceleration than with the old transmission.

I talked to the mechanic who rebuilt it today and he offered absolutely no insight as to what is going on.

Who here knows something out these transmissions and can at least offer some ideas?

BenStoked

iTrader: (7)

fluid at the proper level, not too much, not too little?
$hi#y replacement parts?

Hectic

iTrader: (20)

Wait, you spent $750 to have someone open it up and replace the ISB? Please tell me i'm mistaken. My guess is he took your money and didn't do anything to the transmission. If there's no broken bearings, you're not going to hear anything. So if it's still rumbling, go get your money back and don't take no for an answer. I can see maybe $750 for a complete rebuild, all bearings, synchros and seals. But just to have some guy look at it, replace the ISB, clean it out and make sure things look right? Not so much. I've done that with several transmissions over the years and charge the buyer about $200 assuming they have a bad tranny to trade in.

James92SE

iTrader: (31)

How certain are you that it's the ISB and not just the throw-out bearing?

TOBs commonly rattle with the clutch let out. It can be due to being worn or just cheap. Before selling my original VE 5 speed earlier this year, I actually replaced the TOB because it was a cheapo unit and was rattling with the clutch out, even though it only had a few thousand miles on it.

I specifically replaced it because I knew potential buyers would likely be scared off by it and/or assume it was the ISB. I put in a beefy new TOB and the noise completely went away.

Also - I had the same transmission referenced above rebuilt about 9 years ago. For what it's worth, even after installing the brand new rebuild, it was always pretty noisy with quite a bit of whine in 1st gear. I always figured either I got taken and it wasn't rebuilt or the bearings were just cheap. I haven't gotten an angry e-mail/call yet from the buyer either so I presume it's still going strong

Brad92SE

iTrader: (9)

I agree with James... check the TOB. I've had a couple cheap ones make a whirring noise when the clutch is let out, most noticably in neutral at idle.

1991Maxima1991

iTrader: (3)

i also have the same problem with the noisy chattering tranny, bad part is i just baught mine and it already has this noise but when i installed it i put a oem tob from nissan in it and for the first couple weeks it was fine but then devoleped a chatter through first gear and in neutral...point is even with the factory tob in it "in my case" it still has this noise..Im either thinking that i got a junk tranny or maybe not the right level or type of fluid is in it... ima do some tests on mine this weekend and see what i come up with.. Jw tho when the car is level on the ground and your looking through the spedometer sensor into the tranny where exactly should the fluid level be at?? and also we use gl-4 or 5?

Brad92SE

iTrader: (9)

When the car is level, fluid should be right up to the fill hole in the front. I always just filled it until fluid started trickling out then capped it.

Use GL-4 fluid always, I've heard that GL-5 will eat our synchros. Redline MT-90 (and HD shockproof ) are good fluids that have been known to get rid of some grinding, so they might be able to help with other rattles and noises as well.

1991Maxima1991

iTrader: (3)

well my car is so low i cant really access my front plug.... i go by the top hole in the back of the motor... but anyway wheres the ebst place to buy the redline mt-90? i used the amsoil b4 n i liked it..

Hectic

iTrader: (20)

Expensive oil doesn't fix anything. Might make it quieter at first because the new oil isn't broken down, but the noise is caused by broken bits of the bearing as well as the ***** themselves banging together. It's a waste to pour new expensive gear oil into debris ridden transmission that will need to be fixed soon anyway.

James92SE

iTrader: (31)

Why can't you access the plug? My car is as low as anybody's 3rd gen and I access mine just fine. Just turn the wheels all the way to the left and you can reach right in there just fine

maxitech

iTrader: (7)

Price breakdown: $200 for the junkyard tranny, and the guy charged me $518 parts and labor to inspect the transmission and install the ISB.

I spent $80 on getting 5 qts of AMSoil gear lube express shipped to me (long story), and another $75 on misc parts I saw fit to replace while I had the transmission out. So I guess I am $873 deep in this right now...

The TOB shouldn't be engaged with the clutch out. It is engaged when you push the clutch in to shift.

James92SE

iTrader: (31)

Exactly.. it doesn't/wouldn't rattle/whir when it's engaged because it's pushed up against the pressure plate.

It (potentially) rattles/whirs when it's NOT engaged because it's not pressed up against anything to keep it quiet

maxitech

iTrader: (7)

I am pretty sure I can successfully rule out the possibility of the noise coming from the TOB.

James92SE

iTrader: (31)

If you can rule out the TOB, then I guess the only other explanation is your mechanic ripped you off. Since you bought a core tranny and didn't have the original rebuilt, you really don't even have much to compare it to before and after wise, so from his perspective you wouldn't know any better with the core tranny. I'd bet he didn't even replace anything in the core. Probably just opened it up, didn't see anything "wrong" per se, and sealed it right back up.

shiloh51933

iTrader: (5)

+1

Unfortunately if you can't do the tranny rebuild yourself then you have to rely on some scumbag mechanic who really doesn't wanna put in the labor time and collect your chedder. Bring it back, don't take no for an answer, you want receipts for all the rebuild parts always when you pay some one to rebuild anything. Hate to hear somebody get ripped off by some fuuckin' scumbag mechanic!!

Hectic

iTrader: (20)

Ouch, what did he replace? Did he give you a parts breakdown? The only parts you need to replace the ISB is the new bearing and some sealant. The bearing is about $25 and is not even close to $500 in labor. If you're hearing the rumbling with the clutch is engaged (pedal out) then it is not the TOB, it's coming from the transmission and the guy failed to give you the service you paid for. Pull it out and take it back to him and ask for a complete rebuild because for $500, that's what you should be getting.

maxitech

iTrader: (7)

After thinking about the best way to handle this, here is my plan of action:

Give the guy the chance to either:

1) Remove the transmission and warranty his repair at his shop
2) Refund my money and I will take the second transmission somewhere else to get rebuilt
3) Take him to small claims court if he isn't willing to work something out

I guess the car will get to sit for awhile longer...

CMax03

iTrader: (3)

Where did you take your transmission so I don't make the same mistake using the same liar!

maxitech

iTrader: (7)

I still haven't tried to work something out with the guy who rebuilt the transmission, I think I am just out of energy to put into this car...

The car is sitting four hours away from where I now live, I am working seven days a week sometimes, and I don't have the facilities, time, or energy where I currently live to pull the transmission again.

I really don't know how this will get resolved in the end, but I am thinking that the sale of the car is on the horizon...

Hectic

iTrader: (20)

You have a lot of time and money invested in that car and repairs, sorry to hear this news.

maxitech

iTrader: (7)

Update:

I was in town yesterday, so I took the car to the mechanic that rebuilt the transmission and let him drive it.

He says he didn't realize that you can play with the clutch pedal and make the noise better, worse, or go away completely.

So now he tells me he thinks it may be something like a cracked spring in the clutch disc...I think he is straight up guessing.

At least this potentially means I have two good transmissions...$800 later.

Thoughts on this?

Augustus Maximus

iTrader: (6)

Are you saying you replaced the tranny but kept the old clutch, PP and TOB on there. In that case be glad you didn't sell it when you had it up in the classifed.

James92SE

iTrader: (31)

I've had a cracked/broken/fallen out spring on the disc before, and it caused a horrendous rattling noise. It was so bad that it sounded as if the tranny were going to explode any second. Unless your transmission sounds like it's literally going to explode, I would highly doubt it's a cracked/broken spring. Then again, for it to sound as bad as I describe, the spring would have to fall out and dance around inside the bell housing (which, if it were cracked, surely it would fall out).

It could be a LOOSE/worn spring though. I've had that before too and it caused a rattling noise. I replaced the clutch as I didn't want the spring to eventually fall out and dance around in there as I described above. This loose/worn spring was on an Exedy disc.

I'm with Augustus though, you put the used clutch/tob/pp back on there? I would have at least checked all the springs and stuff. I've noticed quite a few discs over the years with "loose" springs.

Anyway, a loose or cracked spring on the disc certainly wouldn't cause the first gear whine though

maxitech

iTrader: (7)

The clutch, pressure plate, and tob were installed ~25K miles ago. I did not take the disc or PP off, but I did inspect them on the car. The disc has virtually all of its material left and the pressure plate fingers are all in great shape. I made sure the tob spun freely and had no play in it.

vernk

I would go with checking the TOB, one thing to keep in mind, the IPS is not under oil while not moving, it relies on the movement of the gears to bring oil to it so if you start it and just let it sit running with the clutch engaged it will just sit there and run dry, so a idea would be to drive it, then listen to it (be sure not to let it sit and idle very long). Another note: if it sounds the same when cold starting and after it has been driven there is a chance that the oil pick ups have been bent or damaged (not getting oil to the bearing) other then that, how much does the sound differ from clutch engaged and disengaged?

CapedCadaver

iTrader: (8)

well.. i've had the same thing happen, but with different symptoms. my truck's tranny is ungodly noisy due to being 275k old and worn teh **** out so i can't say that it started sounding any worse, but my situation was that the clutch refused to disengage despite the hydraulics working fine.

replaced the hydraulics anyways, nothing. replaced the clutch (omfg miserable job on a 4x4!) and it worked. so.. depending on the failure mode i'd lean less towards the clutch springs and more toward TOB.

Matt93SE

iTrader: (44)

When I broke a clutch spring retainer on my S14, the spring fell out and got wedged between the disc and PP, causing the clutch to stop releasing. I could feel it in the pedal that it was trying, but the car wouldn't fully release.

had to drive it 150 miles home from the track like that too.. fun. every time I had to stop the car, I'd yank it into neutral and stop. when the light turned green, I'd shut the car off, stick it in 1st, push the pedal to the floor (only 1/2 disengaged the clutch), then restart the car and lurch forward. once I got rolling I just shifted without the clutch. yaaay.

when the car was running in gear, it made no funny noises and acted normal. as soon as I tried to push the clutch in is when it started making ugly noises. it was pretty obvious to me it was a clutch issue and not in the transmission.

CapedCadaver

iTrader: (8)

yea that was more or less like my ride home. i only had to go 20something miles, but either way it sucked. the worn-out state of my tranny makes it almost impossible to shift even when the clutch DOES work (takes a good full second to shift from 1st to 2nd at 2500rpm)

Matt93SE

iTrader: (44)

heh.. you should see how sloppy the tranny is in my S14. it's easy to shift, but there's like 3" of play in the shifter. the synchros are so worn, you can pretty much just grab the shifter, do a reasonably close rev match, then pull it into gear. it's nifty.