Transmission gurus...TH350 with no filter for 900 miles, bad news?

OK, so I got a "rebuilt" TH350 transmission and have put about 900 miles on it. It's been working great, shifting fine...not slipping or making any noises. The other day, I started the car('35 Ford 5W) and went on my way. After she was all warmed up and about 7 minutes of driving, I started hearing a noise that sounded similar to someone sticking a wire clothes hanger into a metal room fan and barely making contact with it. The sound was semi-intermittent, and would stop when I gave it some gas..but would return when I was decelerating. As the car warmed up, it got more consistent. So I got home and:

-Checked the fluid level...it was fine.
-Checked the trans./engine mounting bolts, they were fine.
-Checked the torque converter bolts, and checked the flexplate bolts...all fine.
-Checked for a cracked or bent flexplate, it's fine.

So I drove it about 20 miles and it was fine, but then the noise started again. It shifts great, goes into gear smoothly, and doesn't hesitate or skip. Just for the fun of it, I drained the fluid and pulled the pan to install a new finned aluminum pan/gasket(with a drain plug to make my life easier) and do a filter/fluid change. Well, guess what I found:

-THERE WAS NO FILTER! What kind of rebuild is that?

Should I just install a filter, change the fluid, and see what happens? Is it brutal on the tranny if it goes filterless for that long? There were no metal shavings or excess debris in the bottom of the pan, the fluid was nice and red, and the valve body was clean and new-looking. The car idles nice and there's sometimes no noise at all. Any comments?

Thanks in advance,
Adam

 

Well, with as cheap as a filter is, throw one on and go!

I don't think you would have hurt it, since the pickup point was still well below the surface of the fluid, but I'm NOT a transmission guru, and can't make any guarantees!

 

Who rebuilt it? Was it a lot of money? I wouldn't trust taking it back to them but I would defiantly raise some hell. If it was mine I'd run it. TH350's are tough and not to bad to rebuild.

 

Hopefully the sound you heard was the pump sucking air because it didn't have a pickup down in the oil far enough.
If it had the sound of a growling power steering pump running out of fluid, then you should be ok after you put in the correct filter.
I hope you caught it before any serious damaged has occurred.

Let's hope that the small cone-shaped screens that fit into various passages didn't clog up with the junk that the filter normally catches.
If you are lucky, those little cone shaped screens picked up what the filter wasn't there to catch, and hope that none of them gets restricted with the particles.

If your rebuilder put those tiny screens back in like he was supposed to, they probably saved your tranny. If he didn't think they were any more important than a filter..... well, lets hope they are in place where they should be and that the screens saved your tranny from recirculating trash.

 

I know...I wasn't too happy with that. People are forgetful and not perfect, but that's a huge thing to forget! Thanks for all the info/opinions. I think I'll run it...what's the worst that can happen!

 

It is hardly a filter, just a strainer gauze to keep the large chunks out of the workings.

Unless you have thrashed the tranny and got pieces breaking off I doubt you have a problem.

Epoxy a small magnet on the inside of the oil pan, to catch any steel fragments, throw new oil and strainer gauze in, and away you go.

 

if the pickup sucked too much air, then the trans would likely decouple, with no hydro pressure, and then slip. So if you didn't have any slippage, the filter issue is probably no big deal..

 

I'm far from an expert, but my laymans view is I'd put the filter on it and run it and see what happens.

Crap like this is why I'd rather do it myself and learn a new skill even if it costs more.

If he skimped on a $15 filter, what other corners did he cut?!? Plenty I'm sure.

I'd keep an eye out for a core and a good rebuilding manual/video. Hopefully that's not necessary.

Maybe he just set the pan on it to keep dirt out and forgot he didn't install the filter and juist tightened it up later. Or not.

 

If it still works and there are no big chunks in the pan, nothing smells burned you didm't hurt it. Put a new screen on it and happy motering.

 

Put a filter on and run it

 

I like the screen filters verus the ones that look like a dry piece of cardboard some stores sale. Opened a box I got from the local store and half way around it wasn't even crimped down on the cardboard looking type. Took their junk back, plus the screen type flow lots better. Put one on and run it.

 

Looks like the verdict is in...

 

Well, I put the filter on, refilled the fluid, and drove it...it still makes that weird noise. I'm thinking that when it gets warmed up, everything expands and the flexplate might be slightly contacting the little metal, round, 1/4" stopper on the bendix shaft at the end of the starter snout(on the back edge of the flexplate). Has that ever happened to anyone? Could it just be something else totally different and not trans.-related that would make the same noise? The culprit is somewhere down by the flexplate/torque converter and it only happens after I speed up and I get off it and it's slowing down, and after it's been at running temp. for 10 minutes or so...

Thanks, again, for all the info and opinions...you guys are the best,
Adam

 

Oh, and I'm pretty sure the guy didn't mean to leave the filter off...it has a fairly prominent presence under the valve body. I'll give him the benefit of the doubt, this time

 

If it were mine, I'd slap a new filer in it and run with it..

knowing what you know now you will be watching it close, or listening to it closely..see how it goes

 

Done...and drove it to work today, I'm just really anal about stuff like this(but nothing else...in the anal department, that is)

 

Maybe cracks in the flexplate.. around the outer bolts...and some people here say they have seen cracks at the inner bolts to crankshaft.

A slightly mis-rebuilt convertor, welded wrong, sometimes puts stresses on the flexplate causing tiny cracks. Look for dry, dusty, brown colors weeping out around the bolts.

 

cool..did it quiet down?
or stop the noise completely?

 

Crazy question: did you use an inch pound torquewrench on the flexplate bolts instead of a foot pound one?

Any chance of interference with the exhaust or centerlink/tie rods, maybe at fulll left or right?

Just some guesses

Anychance a mechaic stethoscope would narrow it down?

 

No cracks...I removed everything and inspected thoroughly.

I used a ft./lb. torque wrench, and no exhaust or suspension interference...a stethoscope would narrow it down, but it doesn't make a sound when idling...just sporadically when decelerating...

Nope, the noise is still there...it's not constant.

I'll probably keep driving it and see if the noise subsides or lessens...maybe it'll fix itself, right?! Thanks guys!

 

hey adam,
i been building transmissions for 35 years, and done a million 350s, hell iv forgotten a few filters too in my day, i dont even use the little gasket that goes under it, at the correct fluid levil the fluid is way above the filter, thus, no filter = no damage, as long as theres no chunks floating around to get sucked in to the pump. the filter is for catching chuncks mostly.
as far as the noise, nothing in the trannie is gonna do that, id look at maybe the tin dust cover if thats what your running on it.
good luck..

 

Sounds crazy but I'd tighten those torque converter bolts without the torquewrench.

Just get them good and tight with a wrench or ratchet.

Intermittant tapping or knocking is classic loose torque converter bolts. Ask me how I know! The sound didn't happen till after the engoine warmeed up for me either, heck if I know why.

I know I'm not the only guy in the world that's misread a torquewrench when I was *sure* I did it right.

Usually my mistakes are something I'd already ruled out.

Keep us posted and good luck!

 

Thanks, again...I'll retorque those again, and see what happens. As for the dust cover, I'm not running one...

 

I took a tbo350 that I'd removed 7 years ago, been outside, been inna shed and bolted it up and its been 2 years runnin fine. Sounds like a tourque converter bolt to me too.
I bought a 36ft motorhome that the guy thought had a wrist pin was letting go.
It was the flexplate bolt. I bought it for a song with a crate 454 and a rebuilt tbo400.
It wound up being a biz write off for him. Thats why he did it.

 

I just installed a th350 from TCI and it does the same thing. I've heard of a anti clank spring that sometimes does not get put in. Mine drives fine but when the tranny isn't under load, it makes a rattling sound. I checked all the stuff you talked about. I might remove it and have it rebuilt. Problem is now I'm just gitting used to the noise, I don't have a tranny tunnel in yet so I hear evereything.

 

Well, I will definitely go through the TC bolts again, which is a piece of cake as they're way easier to get to than the flexplate bolts...which I should probably re-torque as well.

 

Now you are making it sound like a dented dust cover or cracked flexplate.

I had a transplanted tranny once that did that when the rubber trans mount had a couple years on it and let the trans sag down a slight amount that was enough to start resting on a crossmember that it used to clear.
When the trans started resting on the crossmember, the dust cover started hitting the flywheel teeth when going around a turn.
I started taking corners easier for a while to keep it from hitting. As the mount sagged more, it got harder to keep it from making that "pushing a stick into a fan" noise. I finally changed that mount.
Maybe you have a dented or ill-fitting cover ? Or the engine may be moving around a bit to make the flywheel teeth rub something?

 

Sounds like the same exact thing...and you're in Aptos, so we can drive our clanky cars around together! Where does this spring go that you're talking about? How long have you been driving it with the clanking? I'd like to hear it and see if it's the same thing...

 

No dust cover, and there's nothing anywhere near the flexplate, except for the starter. No crossmembers nearby. I'm going to check it all again tomorrow, maybe I missed something.

 

Hey, I just passed the 1000 post mark!