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Tranny Help

troutbum_mt

1/2 ton status
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The great state of Denial
So for those of you who have been following my blind path to K5'dom and laughing their a$$es off, here's another one for you.

Went and picked up the new Blazer today (the 78 new one lol). Was driving damn nice and I was enjoying the ride so decided to take it out for a little stroll.

Here's a pic of the latest addition to my family when I went to pick it up:

http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0358a.jpg

Here it is in my yard:
http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0359a.jpg

It was driving so nice so decided to take it for a little romp up here:

http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0360a.jpg

http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0362a.jpg

http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0363a.jpg

Me posing as the proud Father:
http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0372a.jpg

Well, went down a trail and everything was good. Transfer case was working sweet, tranny was fine and the thing was handling very well. As I was climbing back up the hill I had a little issue. The tranny popped out of gear and a small cloud of smoke rose up from underneath. It would not shift into any gear, including park. I backed it on down the trail (thank god for Gravity because I was not in the mood to push it) and put some logs behind the tires and let it cool down. I crawled underneath to inspect and found that the bottom of the bellhousing was not attached. I later found it in the back of the blazer :doah:Also, one of the cotter pins that holds the shifter for the transfer case had popped off and I had to temp rig it. No big deal. The thing cooled down, started up, shifted right into gear and away I went.

Well, I didn't get too far before it took itself out of gear again. I was able to limp it a mile or so at a time until I got down the road some.

Here's me begging for the beast to work:
http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0374a.jpg

Here's me PLEADING with it:
http://i239.photobucket.com/albums/ff265/troutbum_mt/DSCN0375a.jpg

Limped it home and am wondering what the hell it can be. It is weird because once things cool down, it runs fine. Then it reaches a certain temp and kicks itself out of gear. This all happened with NO warning either. No weird noises, no weird smells (well, until the puff of smoke). Not used to auto trans and am wondering if any of you experts have any suggestions. It is full of fluid but I am wondering if maybe this is the torque converter or something. I am not used to autos and am just framboozled.

The 78 has a 400 ci engine and the 75 has a 350. Both have TH350s and I am wondering if it is a straight swap. Also, what can be messed up with this tranny? Looks like I get to learn something new here and actually I am pretty stoked about it lol.
Please send more beer and help! :haha:

Warren

PS - Quit laughing at my crappy luck! lol
 
I am going to try and start the tranny and torque converter swap later today. Anybody have any tips, suggestions or advice to give a first timer? The Chilton I have isn't very clear and the 75 Chevy Service and Overhaul Manual Supplement is basically useless without the 74 manual which hasn't come yet. Also, any good books, manuals or sources on how to rebuild a TH350? I'd like to give it a shot even though I will probably end up taking a tub of parts to a shop in the end so they can deal with my failed attempt. Or will that info be in the 74 Service and Overhaul Manual?

To be honest, I don't have the money to take it to a shop and really would like to learn how to do this by myself. I am trying to make this into a vehicle that I built versus just something I bought and paid to maintain and had upgraded by shops. This is more than just a hobby for me. This is going to be my every day vehicle and I want to learn how to do everything for it to keep it on as well as off the road. Being a carpenter, I need a decent vehicle that can handle the weather to get to and from work and want to be the guy that is always there without any problems versus the guy that couldn't make it because his truck was a wuss, broke down, etc. Winter is coming up soon, hunting season is around the corner and I only have a few more days off before I start the next job. I told my daughter the other day that she was going to learn how to drive in one of these Blazers. She is 9.

This isn't a case of "I am too lazy to read how to" it really is a case of I don't KNOW how to and don't have good sources. Would really appreciate whatever tips I can get so I don't screw this up.

I am not used to dealing with automatics. If this were a manual, I would say that the clutch went out so I am pretty sure that it is just the torque converter. I don't have money right now for a new torque converter or a shop so am planning on yanking that and the tranny out of the 75 that I have that I know are good and replacing this "rebuilt" tranny and torque converter in the 78 just so I can be mobile again for work.

Whatever help you all can provide would be most appreciated.

Thanks,

Warren
 
I'm almost positive the transmission and transfer case from the '75 should fit without any issues.

I would highly recommend a quality transmission jack when doing the removal/replacement. Also take the time and support the rear of the engine before you remove the transmission.

Personally, I've never been able to do an automatic swap without making a huge mess with tranny fluid everywhere, including on me.
 
Drain the trans first. It'll make it a little lighter too.


not gonna make it to much lighter, and the trans and converter wont way over 150lbs ive had a 4L80E fall off a jack and i bench pressed it off my chest like a champ, im not that big of a guy. plus i can throw around a 700R4 like a champ too. the convertor is about 40lbs by itself though. if you have access to a decent trans jack its very simple and can be done in all of 30mins when you get some good practice :D i wouldnt drain the trans b/c your looking at 12 qts of fluid to replace. but blow out the cooler lines in your 75 to make sure you dont have any material in them to keep you from messing up this trans. Honestly I dont think its and interal trans problem. Sounds like a linkage issue. But I'm no trans expert, just can swap them with the quickness:D
 
iwaxmyjimmy,

You're a heck of a lot stronger and more daring than I.

I sure as heck wouldn't want to be under a transmission as it falls off a jack. No thank you!

All of us have a different tolerance for risk, but to me anyway, it's worth it to get the right tool and not get hurt. That really takes the fun out of it....
 
Warren, I don't think I've seen you around yet. I admire you for wanting to learn everything and taking the challenge in stride. I'm doing the same, and plan to have my Blazer back on the road, hopefully sooner than later. It'll be restored to somewhat-DD status (I have a company van for work, so I only need personal transportation 2 days a week). I've had to learn to swap the t-case and rebuild the rear axle. Totally worth the time and money I spent on the tools to do it right.

I have nothing constructive to add to this thread, so I'll just say "welcome" and that I'll be following your progress in hopes that you end up with the same result as me. :D
 
The older K5's have a removeable tranny tunnel. If you remove it you can use an engine hoist to lower the tranny to the ground with no risk to life and limb. I use this method for dropping my NV4500/203/;205 as one unit, as well as for installing it.

To the original poster I would go through all the linkages, make sure they are adjusted correctly and all cotter pin's etc are in place. Usually if a tranny is fragged cold or hot won't maike a difference. Your fluid should be a nice strawberry red, at the right level and not smell burnt. If that matches what you have I doubt your tranny is dead. Look for the cheap/simple solutions first.

If your tranny is fubar, there is a great book on rebuilding the TH350. I'll be damned if I can remember the author or title, but I've seen it several times at the parts stores. Prolly 200 pages, and not too spendy.

Rene
 
Warren, I don't think I've seen you around yet. I admire you for wanting to learn everything and taking the challenge in stride. I'm doing the same, and plan to have my Blazer back on the road, hopefully sooner than later. It'll be restored to somewhat-DD status (I have a company van for work, so I only need personal transportation 2 days a week). I've had to learn to swap the t-case and rebuild the rear axle. Totally worth the time and money I spent on the tools to do it right.

I have nothing constructive to add to this thread, so I'll just say "welcome" and that I'll be following your progress in hopes that you end up with the same result as me. :D

Thanks for the welcome and the hope lol I agree that it is totally worth the time to fix things yourself. I mean it is fun to do but also rewarding. Based upon the excellent advice given today, I got all the way down to tearing out the transfer case but I couldn't find a tranny jack so stopped there. Now I am going to follow the advice given and pray that my ultra feeble skills are worthy.

Warren
 
The older K5's have a removeable tranny tunnel. If you remove it you can use an engine hoist to lower the tranny to the ground with no risk to life and limb. I use this method for dropping my NV4500/203/;205 as one unit, as well as for installing it.

To the original poster I would go through all the linkages, make sure they are adjusted correctly and all cotter pin's etc are in place. Usually if a tranny is fragged cold or hot won't maike a difference. Your fluid should be a nice strawberry red, at the right level and not smell burnt. If that matches what you have I doubt your tranny is dead. Look for the cheap/simple solutions first.

If your tranny is fubar, there is a great book on rebuilding the TH350. I'll be damned if I can remember the author or title, but I've seen it several times at the parts stores. Prolly 200 pages, and not too spendy.

Rene

I didn't pull anything today other than driveshafts (was trying to round up a tranny jack) and will go through the linkages tomorrow to make sure that isn't it. It very well could be something simple because the fluid is purdy pink and doesn't smell burnt. While I was out bouncing around, one of the shifter linkages to the transfer case came off. I very well could have put things back together in the field improperly. Like you wisely advised; "Look for the cheap/simple solutions first."

Thanks Rene and everybody for the tips and suggestions. It is really saving my a$$. Will report back tomorrow with the results. Can't tell you how much I appreciate the input.

Warren
 
check all the cables going to the trans. if you were bouncing around you prob jarred it loose. i would put the driveshafts back in and check all linkages and cables to make sure they aint hung up on nething and what not.
 
No weird leaks or noises?

This is the book I had, written by Ron Sessions.

http://www.amazon.com/exec/obidos/ASIN/0895860511/bobthebottoofthe

Rene

Thanks for the info on the book. Sounds like another "must have" for my library. I have bought a Chilton's, the 1975 Chevy Service and Overhaul manual supplement and the 1974 manual (which hasn't arrived yet). But that book is going to help me a lot I can tell.

As far as leakage goes, there is a little leakage from the cooler lines at the fittings along side the oil pan where the the lines join each other, but not much at all. Also there seems to be a tiny bit of fluid coming from the pan gasket. It doesn't look like they used any sealer and it looks like it is soaking through the cork gasket and leaving a little fluid around on the head of the bolts attaching the pan. There is one drop of fluid hanging on the pan and it has been there all day long. No puddle or anything on the ground. I am talking very minimal leakage.

As for noises, yeah I have noticed a weird noise. Idling in park there is no strange noise, but if I rev the engine it sounds somewhat like gears trying to mesh and not fully meshing. It is a weird whirring noise and the closest I can describe it is as somebody putting a piece of paper up to the blades of a fast moving fan or the old card in the bike spokes thing. It sounds normal up to about 3000 rpms and that is when the noise kicks in. It sounds like it is coming from in front of the shifter but behind the engine. I put my ear down to the shifter (no boot) and it sounds like it is coming from the bellhousing. Maybe my ears are deceiving me. It also makes that noise when it drops out of gear and the engine revs up once the gear is gone. But it isn't a grinding noise or an ouch noise like shifting a manual trans into the wrong gear.

If it was the torque converter, would temperatures be a factor in the function? It has me scratching my head because when things got hot, it would come out of gear. When it cooled down, it would run. That has me stumped. I would run it for a mile or so then it would kick out of gear so I would put it in neutral, coast as far as I could then stop on the shoulder. Then I would wait a few minutes, start the engine and shift it into gear and if it engaged, I would go again. I limped it like that for about 15 miles back to my house. Or could it be some sort of electronic gizmo or vacuum issue? Is there some sort of sensor for the cooler that regulates flow that would affect the torque converter? Being used to manual trans, it really is similar to a clutch going out but the whole temp issue has me baffled. The radiator was low and I filled that today too.

It was advertised as a recently rebuilt trans. No mention of who did it, but I know it wasn't a professional. The lower bellhousing wasn't on (it was in the back under a spare tire and some other junk). The rear driveshaft was installed backwards (at least it was opposite of my 75 Blazer). The wires (some sort of 2 slotted plug that attaches to the top of the transfer case shifter) were disconnected. I mean I can tell it was a piss poor job.

Sorry to babble so much, but I want to make sure I give all the relevant info. I'll take some pics tomorrow of the leakage and what not. Maybe that will help some of you more knowledgeable people in a diagnosis because I am stumped. But I plan on going through the shifter alignment process tomorrow in case that is what is wrong before tearing things apart.

Again, I really do appreciate all the help you people have offered. I'm slowly learning and it is a good feeling. CK5 amazes me and I am very glad I came across it and paid for the membership.

Warren
 
check the fluid level when its hot. normally a transmisison will whine when your low on fluid.
 
No weird leaks or noises?

This is the book I had, written by Ron Sessions.

http://www.amazon.com/exec/obidos/ASIN/0895860511/bobthebottoofthe

Rene

Well here is the update. After checking all the linkages, I think I found one source of the problem. The trans shifter was missing some pieces. It is nice having the 75 to compare to. What I found was that the spring and bushing that holds the end of the shifter coming out of the trans was missing. I tried finding replacements at the parts store and was unable to so I took the stuff off the 75 for now. I was pleased that it seemed to shift fine and so started the engine and went through the gears and everything worked fine until I tried to put it back in park. Now it wants to grind and is not shifting into park.

I have tried adjusting things but can't seem to make things want to go into park while the engine is running. If I shut off the engine it shifts through all positions just fine. Did I do something wrong or is there a prob with the tranny after all?
 
Going to go through the shift control adjustments again. I think I might have messed up and that might be what is causing the new problem of not going into the park detent fully or something. The caution in the manual says that "Such operation results in reduced oil pressure and in turn partial engagement of the affected clutches" so maybe that is what is going on.
 
Went through the linkage adjustments again and it didn't help. Still messed up. Sooooo, will be pulling stuff tomorrow hopefully. In the meantime I have been spending time working on some other stuff until I track down a tranny jack. Got the driveshafts all cleaned and painted, been working on some electrical stuff and yanking old, useless wires. Thanks again for all the help everybody. Look forward to getting this thing back on the road.
 

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