Intermediate shaft trans bearing noise?

[Pono]

Hello Ranger Forum,

I have an 89 4x4 Ranger. I put in a new (reconditioned) transmission in thirteen years ago. The intermediate shaft bearing is starting to make some noise. (stops when I push the clutch in) is there an additive I can put in to quiet the bearing as an interim remedy?

Thank you,
John

 

[scotts90ranger]

Which engine or transmission do you have? I don't think an additive is going to fix anything, if it's an M5OD there's roller bearings everywhere but the back of the two shafts. Wasn't too hard to rebuild other than getting a puller deep enough to get the rear bearing off the output shaft...

 

[Pono]

2.9 engine. I know it was replaced with a Mazda trany. I will try and get the model.

 

[scotts90ranger]

If it doesn't have a steel pan on the bottom of the transmission and it looks like the bellhousing is one piece with the rest of the transmission that would be a Mazda M5OD.

Pushing the clutch in unloads the gears even though everything is spinning, is the noise louder in any particular gear? Mine was loud in 3rd and 5th mostly but quieter in 4th which is the only gear the countershaft isn't loaded in which narrowed it down to a bearing on the output shaft and sure enough the tapered bearing on the output shaft was FRIED, if it's anything like mine was there's no additive on the planet that would make a dent in what was going on. If there's bearing noise it's just time to refresh it, it was $150 on Ebay for the rebuild kit, about $100 for new slave and master cylinder and then $60 more for the parts I needed that weren't in the kit, and $250 for a clutch I probably didn't need to replace, I'll measure that tomorrow...

 

[Josh B]

Seems you're tween a rock and a hard place there bud, and I don't think a patch is gonna fix it either.
How many wrecking yards you got in Hawaii? Even if you do find one they claim to be good they're gonna want an exchange :/ If you had a good friend that can rebuild one you might get lucky there, and that might take some time. The fastest would be if you found one that could be used while you got them to rebuild it at least would keep you in a vehicle.
Scott has some good ideas about it too tho

 

[gearfather]

if the noise goes away in 4th gear then you have a bad input and cluster. in 4th gear the power goes straight thru. there is no load on the cluster being that your input is 4th gear. if you are looking in the boneyards, keep in mind that you can use a trans from a 2.9 or a 4.0. ..88-97 ranger 2.9 or 4.0...91-97 exploder...91-97 mazda navajo...mazda b4000. and the freak, 88-90 bronco II 4X2 (they used a 4x4 trans with a dummy transfer case behind it, just make sure that it is the mazda trans...

 

[Shran]

I don't see that you mentioned whether this noise occurs while moving or stopped or both. It is kind of normal to hear some gear noise if the truck is stopped, trans in neutral, clutch engaged.

The noise gearfather mentioned in my experience is an annoying whine and only while moving and in every gear except 4th. "normal" gear noise when idling stopped in neutral is more like a soft low pitch whirr. There are other things that can rattle and make noise under the truck too and those should be ruled out before you diagnose a bearing failure in the transmission. Even something like the foam piece under the shift boot can allow a lot of noise to come into the cab if it disintegrates.

 

[Pono]

Good Info! The shop that replaced the tranny in 2009 said it is either a M5R1 or M5R2. Will diagnose more with the posts above.
Has anyone used the Lucas Heavy Duty gear oil SAE 85-140?

 

[Shran]

Good Info! The shop that replaced the tranny in 2009 said it is either a M5R1 or M5R2. Will diagnose more with the posts above.
Has anyone used the Lucas Heavy Duty gear oil SAE 85-140?

It's an M5R1, the R2 was the full size truck (F150/Bronco) transmission. Similar but not the same.

I would not put gear lube in it. Dex/Mercon III ATF is the factory spec oil, some people also will use 5w30 synthetic engine oil or Syncromesh MTF fluid in it. Not gear lube!

 

[Pono]

The last shop that replaced the gear oil used the typical 80-90 gear oil.
Looking at the manual it states if Mazda transmission use Mercon ATF. interesting...

 

[Shran]

Gear oil is (a) way too heavy/thick for this type of transmission and (b) contains additives that are corrosive to brass/bronze/copper, IE the syncros in your transmission. It is fine to use it in older transmissions but not ours. Lots of people simply don't know better.

 

[Josh B]

Why do some use the 5W30 synthetic. any good reason to it?

 

[Shran]

Why do some use the 5W30 synthetic. any good reason to it?

It is thicker than ATF. So if you have worn parts, it can somewhat help to fill loose tolerances between things - bearings, syncros, etc.

Some of this depends on what climate you live in, really thick oils are not appropriate for manual transmissions in cold places because they will not flow throughout the case as they should. On the M5OD for example, oil is slung up and into a little trough that feeds the input shaft bearing. No oil getting slung into the trough... no oil in the bearing... you get the idea.

 

[Josh B]

Wish I had known that before, actually the older original is still in it, but weather permitting it won't be much longer. It was making some noise one night trying to navigate rush hour traffic one Friday over in Texas so I've been trying to go easy with it. Maybe I should go ahead and get the rebuilt one in there, doubt it would be a whole lot more involved than in doing them together

 

[Pono]

Determined the trans is a Mitsubishi M146. Which uses gear oil. Has the 12 bolts holding the oil pan on. Today should have been an easy oil change but the prior shop I had change the oil last over tightened the fill plug so now it is stripped. Vice grips would not do the job or a pipe wrench. Will try and locate the bolt extractor socket. Unfortunately I drained the oil prior to removing the fill plug. Might consider removing the shifter from the top to get oil in the trans so I can drive it to the shop to remove the stripped bolt.