rattle location

[alg8er]

'93 VR-4 stock drivetrain, as far as I know, with 105,000 mi. I have a rattle that's audible only in neutral. As soon as I press the clutch pedal to the floor, the rattle disappears. I assumed that it would be the throw out bearing. My mechanic put the car on the lift, and says it sounds like it's coming from the tranny. If it is the tranny, what could cause a rattle? The car runs fine, and pulls strong in every gear.

[Valhallaz]

The throwout bearing is in the transmission bell housing. That would be my guess also.

[Austin@STM]

Usually the throw out bearing. Epescially if its still the stock clutch.

[DocWalt]

It's not likely the TOB, more likely just the trans rattling. Common Getrag problem.

[Hans@GZP]

They rattle a lot. Could be the TOB, or the input shaft bearing. Those are the 2 most common reasons for a trans rattle.

[alg8er]

It's not likely the TOB, more likely just the trans rattling. Common Getrag problem.
LOL! Just the trans rattling. Well that puts my mind at ease! :-D

[alg8er]

Thanks guys! My mechanic was worried he wouldn't be able to tell what was rattling once he pulled the tranny/clutch, if it wasn't the TOB. I planned on a new clutch anyway, but I'll have him look closely at the input bearing. So what's a good street clutch for a stock motored VR-4 these days?

[DocWalt]

f the TOB was bad, it would make noise when you pressed the clutch in. If it rattles when the clutch is out... oh well. The input shaft bearing is a good thing to inspect when it's apart, for sure. If you decide to replace it, definitely get an OEM one if you can. The knock offs suck, and fall apart.

I'd go with an RPS Max with the Street disc, feels similar to stock because of the full face organic disc, but has the grip to hold a good amount of power.

[Austin@STM]

TOB can rattle when not pressed in because there is no pressure on it so it just floats around on the shift fork. My clutch, tob, pivot ball, and fork were all new this year and still got some good rattles sometimes if the clutch pedal wasnt down.

[alg8er]

I really hate those "lets tear it down and see what's wrong" scenarios. Any other tests I can do to narrow it down while the car is running? Now I'm wondering if it's input shaft bearing and/or tob, do I even need a clutch? With 105k, if I pay for the teardown anyway, is it stupid not to replace the clutch no matter what?

[DocWalt]

Austin, if the TOB rattles only when the clutch is out, it doesn't matter, like you said. You're certainly not worried about it rattling, are you? :p

If you're tearing it apart, it's stupid to not replace the clutch, IMO.

[alg8er]

Doc; "If you're tearing it apart, it's stupid to not replace the clutch"
Worse yet, I'm PAYING to tear it apart. Just looking for a cheaper way out. Wrong vehicle for that! The RPS clutch is way too much $$$ for me. Sorry, I should have stated my budget. I don't want to go too cheap, so how about a midrange, like under $500 for the whole kit?

[alg8er]

do you have to open the tranny to inspect / replace the input shaft bearing?

[DocWalt]

I don't really have an answer for either of those questions. If you're not gonna go around launching your car, a stock clutch would be fine. I don't know about the input shaft bearing, if the trans needs opened or not.

[Hans@GZP]

If you are keeping it under 450 hp, I'd stay with a stock clutch setup. They should run around $300 from Cherry Hill Mitsubishi. If you are looking for an upgraded clutch, I can get you a good deal on a South Bend Clutch for sub $500

[alg8er]

Not planning on 1/4 mile launches or modding, so stock clutch it is. Thanks tons for all the help guys!

[alg8er]

TOB was fine. Clutch springs were very loose and rattling. Also the input shaft seal on the tranny was leaking slightly, coating the clutch with a thin film of oil. So.....in order to change the seal, the tranny has to be opened. I might as well replace the input shaft bearing, and the 1,2, and 3rd gear synchros while I'm at it. So much for a cheap job.

[MaxClass]

What type of Transmission fluid were you using because I don't want to use the same stuff if I can help it?

Could the internal problem be due to low fluids?

[alg8er]

Maxclass; sorry it took me so long. I'm not sure if there's internal damage. The seal hasn't been pulled yet, so I'm not sure if it's a failed seal, or just fluid leaking past. The leak is very minor, hardly any oil gone. When I bought the car about 50k ago, the 2nd and 3rd synchros weren't perfect, and it was my daily driver, so I had to put in thinner oil for occasional (no salt) winter driving. With the new clutch and synchros I'll be going back to spec oil.

[alg8er]

the inside of my tranny is perfect. Looked like it was brand new. Synchros look brand new, and all teeth, gears, and other seals are like new. Clutch plates looked like new, besides the oil coating. Was it a coincidence that the clutch springs started rattling just before the seal started leaking? I lived with a light rattling for about 6 months, before it started getting worse. Then about a week later the clutch started slipping under hard acceleration after an hour or so of driving. I'm baffled, and broke.

[DocWalt]

The clutch springs rattling was likely just a coincidence. I'd replace the seal and buy an OEM clutch disc and call it a day. Make sure you get the flywheel resurfaced if you do that, and they have to get the flywheel step right. The proper two step height is: .827" +-.002

[Pensky3thousand]

The resurfacing is key. Just had two done locally by a machine shop. 43 dollars. Dropped it off in the morning and picked it up in the afternoon. 20 year old flywheels with a fresh cut ftw lol.

[alg8er]

flywheel resurfaced, Exedy OEM clutch, and new tranny seals. Car drives smooth again, no noises, but the clutch pedal has hardly any resistance at all. I'm wondering if the old clutch was a stage one. I haven't pushed it yet, still breaking in, but it seems to hold well. Pedal play, and grab point are correct, just feels light compared to last clutch.

[DocWalt]

The old clutch may have had a different fulcrum point in the pressure plate or something that caused it to be heavier. Obviously not a stock clutch if it was super stiff.

Sounds like you've got the problem licked. :)

[alg8er]

Doc; It wasn't real stiff, but the new clutch is very light. Lighter than every clutch in every manual car I've ever owned, and they were all stock clutches. A 12 year old girl could use this clutch. Just hard to get used to.

[DocWalt]

We have clutch boosters (like a brake booster) on the clutch which makes them lighter feeling than they are. That could cause it to feel really light. It's been a year or so since I drove a buddy's VR4 with a stock clutch, so I can't remember how it felt.

[alg8er]

I pushed it hard today, and no slip at all. I guess this clutch will be fine. Thanks for the help everyone! Doc, I've never driven a VR4 with a stock clutch (apparently), so I have no comparison. I forgot about the booster.