sgi02

Please be easy on me. Just picked up my first RX7! A 1993 VR R1. I love the car to death , but I have had one issue that I haven't seem to have found a good answer for.I searched and read the FAQs , but didn't see, to come up with much relevant information.

I took a flight to pick up the car and drove it home. The drive home went great , but after 5-600 miles into the trip home I noticed a high pitched whine coming from the transmission. It only happens in 1st , 2nd , 3rd gear. It gets louder at higher RPM's . The strange thing is that 4th and 5th seem just fine and do no ommit this noise.

I have allready ordered some Redline MT-90 to flush out the transmission. Any ideas what this might be or what I should look for? The car still shifts fine and dosen't seem to be slipping. Thanks in advance for your help!

c00lduke

Does it stop if you push the clutch in?

sgi02

I'm pretty sure it does.

dgeesaman

iTrader: (7)

I'd have to guess it's a chipped gear. Drain the oil. Then remove the lower cover (with all the bolts), have a pan below to catch oil dripping. Look for chunks of steel on the magnet, or any other signs of things gone wrong.

I would keep track of the noise and if it gets any louder, get the tranny changed out.

Dave

GoodfellaFD3S

iTrader: (213)

Sounds like the main bearing on the input shaft. 4th gear is a 1:1 ratio, thus you won't hear any noise in 4th. I had the same problem with a used tranny in my fc vert.

dgeesaman

iTrader: (7)

Rich, I have yet to see an input shaft bearing that made no noise when cold, but got noisier when hot. But it's definitely a possibility.

HDP

iTrader: (2)

Back from the dead... my new (used) tranny has this same issue. Whines in 1st, 2nd, 3rd and very lightly in 5th, no whine in 4th. So, what is involved in replacing the main input shaft bearing? Is it worth it to repair this tranny or try to find another one?

dgeesaman

iTrader: (7)

It's entirely possible that your bearing problem is the needle bearing between the mainshaft and input shaft. That one stops rotating in 4th, and in 1st it sees the highest rotational speed.

Replacing the main input shaft bearing is not bad, but that needle bearing is a full teardown. Not to mention that input shaft rear needle bearing uses the input shaft and mainshaft as an outer and inner race, which means both of those are probably worn too.

Now don't take this diagnosis as the Word. But it's a strong possibility given your specific symptoms.

Dave

HDP

iTrader: (2)

So it's possible the tranny I received is no good?

dgeesaman

iTrader: (7)

Possible.

GoodfellaFD3S

iTrader: (213)

This is the reason I chose to have my existing transmission completely rebuilt back in 2003 by a professional shop. Less money and time spent in the long run, it's been bulletproof ever since....(i also cryoed all my synchros for the hell of it)

HDP

iTrader: (2)

Soooo... is mine worth repairing or should I just try to get another one?

pinkrx7

iTrader: (2)

getting another used tranny could bring the same problem. Rebuild yours to be sure.

dgeesaman

iTrader: (7)

Rebuilding can be expensive, easily to cost of a few good used trannys.

If you have a worn bearing where I suspected, you'll need a new input shaft, mainshaft, and all new bearings and seals. That's $1000 in parts from Malloy. Then factor in the rebuild cost, probably another $1000. If you're willing to invest in good hard parts you'll have a very solid tranny.

But then again for $650 you can get a low mileage tranny that's probably just as good. Probably.

HDP

iTrader: (2)

So will driving the car in this condition pose any serious harm or danger until I can locate another tranny?

dgeesaman

iTrader: (7)

Nope.

DaveW

The whine is, as others have said, due to a worn bearing, which causes the gears to mesh incorrectly. This incorrect meshing of the gear teeth produces the whine.

dgeesaman

iTrader: (7)

This is a good point - in 4th none of the gears are loaded, which would silence any gear whine. Unfortunately, again you'd need to tear down and rebuild the transmission to fix that.

Dave