Damaged input shaft bearing?

[rkdoty]

Hello everybody!

I’m a new owner of an 85 SR5 4wd wagon, manual transmission. I’ve only had it for about one month, haven’t driven it more than ~400 miles. In the last 50 or so miles of driving it’s developed a ticking noise that’s in sync with the engine rpm’s. It was very faint at first, and I couldn’t tell where it was coming from but now it’s quite loud and definitely coming from the transmission. After going through many posts on this site, it sounds like it’s the input shaft and/or input shaft bearing…? It’s very noisy (ticking noise, not grinding) with the clutch pedal up, and when the clutch pedal is depressed it goes away. If this is the input shaft bearing, or shaft itself, the main predicament seems to be finding a replacement. Is my best bet simply finding another transmission? Either to salvage parts or swap entirely?

Any advice/direction would be greatly appreciated. I’ve wanted one of these cars for years, and was super excited to find a real beauty! Hoping I can get er back the road soon

Thanks!

-Ryan

[dlb]

I agree that sounds like the input shaft bearing. I think there are two on this trans, one that is accessed from the outside and one you can only access by disassembling the trans. I'm not positive about that though so do a search here for more on that.

Anyway, have you checked the transmission oil level? If it's been driven with low gear oil, that will kill the trans fast. Very important.

edit: just found xirdneh's very useful write-up on this: viewtopic.php?p=117793&hilit=input+shaft+bearings#top

[rkdoty]

Hey thanks for the confirmation. Seems like pulling the transmission is the easiest way to replace. I’ll be checking and filling (if needed) the transmission oil today or tomorrow to see if that might make a difference…? I recall reading one post where that did get rid of the noise

[NWMO]

Ryan,

When the input shaft is spinning (even with the transmission in nuetral) there is at least one gear (idler gear I believe) that spins as well. I have had three transmission failures, none involving the input shaft. Just my experience.

Chris

PS - I’ve pulled the trans by itself twice, but last time I pulled the front diff/trans together. I believe the time/effort is about the same, but I got a much better seal and less leaking when pulling/replacing together.

[rkdoty]

Hi Chris,

Thanks for responding. I’m encouraged to hear that input shaft troubles are not necessarily a major cause for concern. Also, good insight on efficiency when pulling trans and diff together. Less work in the long term—I reckon—to do a little more more work now.

[SirFoxx]

Hi Chris,

Thanks for responding. I’m encouraged to hear that input shaft troubles are not necessarily a major cause for concern. Also, good insight on efficiency when pulling trans and diff together. Less work in the long term—I reckon—to do a little more more work now.

to contradict chris, while pulling the unit as one is easier, it is a huge pain to get back in as a whole unit, unless youre good at deadlifting ~100-150lbs. i always split mine from the bell housing. less work to do so (dont have to disassemble suspension, pull axles, etc.)

also shameless plug, if you need gaskets, i do make and sell them.

[dlb]

I have only removed and reinstalled the trans and diff together a number of times, but I use a big rolling jack to do so. I'd probably look at separating the trans and diff if I were in a different working situation.

[rkdoty]

Gotcha. I suppose I’ll cross that bridge when I arrive to it. For now, I drained the gear oil (which was low) and it was pretty much a gob of silver sludge at first, and a piece of a gear tooth came out with it. I’m feeling pretty hosed now.

Feels like a death sentence for this trans… any input is again, greatly appreciated.

[dlb]

Sorry rkdoty, that's a bummer. How many litres came out of the trans?

I went through the same thing with my most recent Tercel. I had another trans but it was from an '83 so it had the different gearing. Had to swap diffs before putting it back in the car. Be aware that you might have to do the same if you get a trans with different gearing.

[rkdoty]

Not quite sure how much came out. Have yet to measure. Also, good note on the diff swap. Hoping I won’t have to, but good to know. Fortunately the previous owner has the original trans. The one I got was a replacement. Not sure of the reason for replacing, but I’m gonna pick that up in the next week or so. Here’s to hoping I (or someone who knows better) can Frankenstein a good one between the two.