Just a little background info; The transmission is in a 77 Chevy K10. Fluid has been changed and the level has been checked and is fine. The previous owner never changed the ATF and it was burnt to **** and smelt HORRIBLE and had some shavings in it. I was told by him that when in reverse it will sometimes make a LOUD Squeeking sound. Since this is yard/work truck i wasnt to concerned because its just going to be used to haul wood and i figured id deal with it when the time comes. Well that time has come.

Today i backed it up to my shop to remove the tailgate to straighten it out after it got smacked around and it hardly wanted to back up. It made a loud squeek sound (It didnt sound like grinding at all, really a squeek) and creeped its *** backwards. Its had some problems before with reverse. When put into reverse it almost acts like it doesnt want to move, almost like the brakes are applied and your trying to back up. Sometimes it takes a minute to get into gear. When it does it seems like its hitting so hard that i'll watch the rear wheels bounce around (can you say "wheel hop"), weird huh? It probably didnt help backing up a hill and im guessing i killed it.

All other gears work fine. It will go into reverse (atleast i think). I can hear it click. When in said "Reverse" you can sit there and rev the **** out of the engine and it wont move, like its in neutral. I checked the vacuum line(s) and everything seems find, could it be the modulator? or is it completely shot and needs a rebuild? Could the valve body be gummed up since it wasnt cared for? Should I check out the linkage and take a better look instead of assuming?

Im not 100% famaliar with Automatic Transmissions. If you need any more info let me know.

Let me add something real quick. I do not know for certain that 3rd works. This truck isnt registered or insured so its not street drivable (legally anyway) and i dont have enough cleared property to see if it goes into 3rd. I have gotten it into 2nd so i know that works. When put into 1st it will SLAM into gear, pretty hard and make the whole truck jump forward.

 

If you put the transmission in Manual first gear (1 on the indicator) do you have engine braking?

 

I havent tried so i dont know. Could you give me some info while your at it? Lets say I do, then what? If i dont, then what?

 

Since i cant drive the truck on the street it will be hard to tell if the truck will slow down from engine braking. I can try on my drive way since its fairly long but being gravel it may not do much justice.

 

It's probably the low roller, it breaks from getting stuck and rocking it from drive to reverse.
It sounds like you broke it enough to just cause it to bind up, like just cracked the outer race. Doesn't sound like it blew all the rollers out yet.

 

ok after doing alot of research i discovered that the low/reverse roller clutch is what will give you "engine braking". When i get home im going to try and find a flat enough surface to see if i get any engine braking. If i dont i guess its safe to say i destroyed the roller clutch? Im going to get a handbook and tackle this myself. Ive always wanted to do an auto so i figured i got nothing to lose now. Either way id get stuck taking it somewhere to get rebuilt. Why not make a learning experience out of it?

 

Not really. In a th350 it's the band that gives you engine braking. It's the only thing the band does really.

 

ooohh ok. Thank you!

 

Incorrect, there is only 1 band in a th350, and it only gives you engine braking in manual 2nd gear. The th350 uses low/reverse clutches (a th400 uses a band). the low roller clutch doesn't do anything in reverse. The low reverse clutches give you reverse, and engine braking when in manual first.

 

I don't know the purpose of the guessing games and posting over who's right or who's wrong. Anyone who knows anything about the description of the problem should just say take the trans out, take it apart, and fix the problem.

It doesn't matter what broke, it needs to be taken apart to be fixed.

I never said theres more than one band in a th350.
The low roller will do something in reverse if it's broken, I've seen chunks of **** from a failed one stuck in the low clutch, etc. No one can predict what failed, it's all a guess until you take it apart. We can talk all day about what does what in a th350, but add broken parts stuck where they don't belong and even the best transmission builder can't accuratly predict what broke.

 

No needing in getting pissed, I was just correcting bad information. Yes, it needs to be taken apart to be fixed.

He asked what could be wrong. If there is no engine braking in manual first, and reverse doesn't work it probably smoke the low/reverse clutches.

 

Thank you both for information. Since i havent been inside an auto i was just looking to gain some knowledge on what to look for (and/or what im in for) and your right it does need to be taken apart to really know what bit the dust. I just got the tranny out today and boy was it a bitch. The cast iron transfer-case didnt help any... mainly caused all the troubles on trying to figure out the safest and best way to support it while I unbolt and drop it. Trying to take it down in 2 pieces seemed almost impossible because of the bolt locations between the two and how ******* awkward it is. Putting it back they will be seperate, atleast now i can clean it and see where the **** everything is.

Now onto the good stuff! I only changed the ATF about a week ago and hardly even used the truck except that day when reverse went out. The fluid (the new fluid i put in about a week ago) was TOAST. Completely burnt again! and to NO suprise metallic flakes and chunks settled in the pan and in the filter. So something is totally FUCKED. My father insists on taking it somewhere to get it fixed because they will guarantee their work and if i do it myself i have only I to blame. Im going to speak to the guy tomorrow and see what he says. Since its out already im hoping to safe alot and get a good deal on the repair. Ill keep posted as the project continues and relay information to see if the guy is telling the truth or is full of ****.

 

The th350 uses the low and reverse clutch and the direct clutch for reverse . If either one is fried it wont back up . If its the low and rev clutch , it will onlt effect reverse and engine brakeing in low . If its the direct it will effect 3rd gear .,But it doesn't matter which . It does have to come out . If you don't have the tools or experience to change or at least check the seals and drums you are better off leaving it to a pro . Since its a 4x4 and a pain in the but to pull and re install , you probably don't want to do it more than once .
If I can help with any questions you may have feel free to give me a call .
John Orlando @ Big John's Transmission 817-281-9230