Input Shaft Bearing Troubles

[pattygook]

Patrick here again with my latest problem.

'87 Bronco II

2.9 Manual

I did a clutch job a couple years ago and it looks like there was a very minor leak. I got in my bronco a couple weeks ago and noticed the input shaft bearing was whirring pretty loud. I hadn't noticed it before because of a noisy alternator belt or something. I was out of town, so I drove it to the nearest jiffylube and got them to refill the transmission fluid. It was a quart low (out of 3 quarts). After they topped off the fluid, the whirring sound was still there, but not quite as loud. My question is: Is the input shaft bearing something I could run until it dies, or should I replace it ASAP. I'm not sure if it's one of those things where if the bearing breaks, I'd need a new transmission. It's starting to rattle a little bit after long trips, so I'm stopping every now and then to let it cool down.

 

[FordBroncoII]

Patrick here again with my latest problem.
'87 Bronco II

2.9 Manual

I did a clutch job a couple years ago and it looks like there was a very minor leak. I got in my bronco a couple weeks ago and noticed the input shaft bearing was whirring pretty loud. I hadn't noticed it before because of a noisy alternator belt or something. I was out of town, so I drove it to the nearest jiffylube and got them to refill the transmission fluid. It was a quart low (out of 3 quarts). After they topped off the fluid, the whirring sound was still there, but not quite as loud. My question is: Is the input shaft bearing something I could run until it dies, or should I replace it ASAP. I'm not sure if it's one of those things where if the bearing breaks, I'd need a new transmission. It's starting to rattle a little bit after long trips, so I'm stopping every now and then to let it cool down.

My old Bronco II 1987 transmission used to rattle but not excessively. It never made any other noise. Then one day oin the highway it started leaking transmission fluid and and all gear shifting ceased. As it turned out when the transmission was pulled-out after being towed (towing charges) to the repair shop, it was broken metal inside the transmission housing. The mechanic put in a used transmission instead of the new $1300 transmission. The used one was $350 plus labor charges, In the process, I installed a new Master Cylinder at home, even though it was not the clutch but the transmission.

Perhaps someelse can address the whirling sound, because i am not sure that is a transmission,

 

[Jimmy Neutron]

The transmission fluid leak is what is throwing me off...

I can understand a brake or hydraulic leak interfering with shifting, but not a transmission fluid leak. At least not with a standard transmission that has a hydraulic clutch.

Are you 100% certain it is the input shaft bearing? I am not very familiar with any of the standard transmissions that were installed in Bronco II's (4-speed Mazda TK4, 5-speed Mazda TK5, 5-speed Mazda M5OD-R1, 5-speed Mitsubishi FM145, 5-speed Mitsubishi FM146) but am quite familiar with what was installed in the 2003-04 Mach 1. With the T3650, it is nearly impossible to wear out the input shaft bearing, but just with common use the throughout bearing fails. Also, (I may be wrong here) I think the input bearing does not receive lubrication from the transmission.

Does this noise go away with slight to moderate pressure on the clutch? If so, I would suspect a throw-out before I would an input shaft bearing.

In any case, with any bearing there is possible catastrophic damage when whatever the bearing is supposed to support wears through the inner race, the bearings, and then the outer race. At that point, the material holding the bearing is damaged, usually beyond reasonable repair.

Some gear noise (whirring) from a standard transmission is normal when the fluid is low. Once this noise is heard, you may be listening for it more than usual, which is making it more apparent to you. Is it possible that this noise was always there?

Also, if the fluid was low for an extended period of time before it was noticed, the gear mesh could be off inside the transmission. Running with low fluid is like putting excessive mileage on the transmission, therfore aging it before it's time.

Hydraulic fluid (brake fluid) leaks would lead me to believe that the hydraulic servo that operates the clutch fork is failing. Again, I am still trying to figure out the correlation between the transmission fluid and the transmission failure. Standard transmissions will operate 100% empty. Not well, but they will operate.

Metal inside the bell housing could be a failed clutch... or throw-out bearing. I am not trying to discredit the repair shop that replaced your transmission, just making sure that the people that read this will not jump to the belief that metal in bell housing equates to bad transmission.

I hope this answered more questions than it created!!

~J

 

[Elmo]

A decision of RTF-run to failure in reguards to ANY bearing has a large possibility of resulting in severe damage to any and all related parts. When ran dry the input bearing on a M5OD can weld it self to the input shaft and either strip all the teeth off the gear side or snap the shaft off on the clutch side. I have seen it happen both ways. But as stated before with being ran low,although i am not sure 1 qrt low is low enough to starve the bearings of ***** the trans gears are subjected to accelerated wear and with the miles that would already have been on an 87 the wear may be to the point that the noise is not going to go away short of a rebuild. I have had some luck rebuilding my own M5OD and have gotten good service from Kormex trans look them up their $$$ are really good.

 

[pattygook]

I just assumed it was the input shaft bearing because of the fact that when I push the cluth in, the whirring sound goes away. I haven't really experimented to see if it goes away from partially pushing the clutch in, but as soon as I can, I'll post the results. I do have a 5-speed FM145.

I know for a fact that the noise has always been there, but until recently, you had to shut off the radio and really listen to it to hear it. When I did the clutch job, I went ahead and replaced the ***** cylinder, since it was internal to the transmission. I haven't personally seen the leak, the guys at jiffy **** simply told me it was near the front, but I haven't had time to actually look for it and verify it.

If an RTF will result in a rebuild, then I might as well make some time to pull the transmission and replace the bearing. But I'd like to know for sure what needs replacement before I put it all back together and having not fixed anything.

Thanks everyone for your .02.

Patrick

 

[pattygook]

I just tested it out and you definitely have to push the clutch all the way in for the noise to go away.

 

[Jimmy Neutron]

Are there any local transmission shops that give free estimates?

There is around here, and I give him $20 for the diagnostic if I end up fixing it myself.

 

[pattygook]

Are there any local transmission shops that give free estimates?There is around here, and I give him $20 for the diagnostic if I end up fixing it myself.

Yeah, there's a real good one where I'm from. I think I'll pay him a visit when I get back into town next week.

Thanks for the advice,

Patrick

 

[andre]

THERE TWO COMMOND LEAK ON FORD AND MAZDA TRANMISSION ONE IS UPPER TRANMISSION CASE COUVER WHERE GEAR SHIFT IS

OTHER IS PILOT SHAFT BEARING SEAL LEAK

LOOK BETWEEN CASE AND ENGINE IF THERE A LEAK THAT PILOT SHAFT SEAL THEN THE BEARING THAT HOLD THAT SHAFT IN TRANS HAS PLAY NEED TO REPLACE IT THAT BE YOU'RE NOISE

OR ON TOP OF TRANS THAT UPPER CASE SEAL OR GEAR SHIFT SEAL

IF YOU DRIVE AND HAD LITLE PRESSURE ON CLUCTH AND NOISE GONE AWAY THEN CLUTCH BEARING

HOPE THIS HELP

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