Transmission Disorder
 

2001 Blazer 150k miles

First I would like to say I bought this knowing the trans was bad. I am not sure of too many details except that this is the second trans for this vehicle and it has about 75k miles on it.

I was going to use the car for parts but if I can fix it I will have a nice 4 wheel drive to use as a DD or whatever.

After I trailer-ed it home I tried to run it and after about 20 minutes it would loose all forward and rev movement.

I changed the fluid and filter.

Attachment 30910

Attachment 30911

The fluid did not have metal flakes in it and does not feel gritty. It does look kind of brown, kinda like clutch material.


This got the trans working again, but now there is a chatter/buck and some slipping when I get over 55mph at a steady cruise. I found a nice stretch of road to test this out. It does this in 3rd and 4th gear.

My guess is the 3-4 clutch pack is worn out.

Has anyone dared to go into the trans and rebuild? If so would you mind sharing your experience?

Thanks


Attachment 30912

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i bought my 93 with the same issue, has all sorts of 3rd and 4th gear issues. since my truck is a off road only truck i just ignore those gears. 7 years later that trans is still working fine

I rebuilt mine myself not knowing anything about it. After searching youtube and other forums I had enough confidence to do it myself. Wasnt as hard as people think. The hardest part was getting it out. Took one day to rebuild and one day to reinstall. 7000 miles later its still going strong

Make sure you get a new torque converter built for it. i would never re-use the old one. It has as much if not more crud in it as the trans did. And flush the lines and cooler too.

That's cool, good to know these are tough transmissions. I really want this one to work correctly if possible.

Exactly what I wanted to hear, thank you. Glad it's still going strong. This gives me the confidence to take it on.

Yes I will definitely do this. I thought about reusing it as is but like you say all the old crap is still in there. I know of a place locally with a good reputation I can use.


Thank you everyone for your input.:icon_beerchug:

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Update
 

OK so I'm a slow worker.

I decided the trans needs to come out and started the disassemble y. I removed as much as I could before removing the cross member. The stater was the hardest to get out, now I know how to do it, still a PIA but I found a little easier method.

https://blazerforum.com/forum/attach...ine=1432599401


https://blazerforum.com/forum/attach...ine=1432599401

https://blazerforum.com/forum/attach...ine=1432599401


A little more work and the trans will be out, and on to phase 2.

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Glad your taking it on yourself. You can do it take your time

Thanks, will do. I'll update as I get more done.


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helpful video

Wow, thank you sir.

I may also have some questions along the way.


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I`ll do my best

It's out
 

Took some time and built this stand that bolts to the jack.

https://blazerforum.com/forum/attach...ine=1433197146


Worked pretty good. I was able to ease it back and down without dropping it.

https://blazerforum.com/forum/attach...ine=1433197146



Next up is the rebuild.

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I used a milk crate, yours is much better

Don't laugh but it took me a few hours to build that. There's a piece of steel on the bottom and it's all screwed together. Na, it's OK you can laugh.

I was gonna use kerosene to clean the internal parts during disassembly . If everything looks OK I'll get a good rebuild kit.

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Disassembly
 

https://blazerforum.com/forum/attach...ine=1435377123


https://blazerforum.com/forum/attach...ine=1435377123


https://blazerforum.com/forum/attach...ine=1435377123


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Teardown
 

did you find your failure?

Great question
 

I can't say definitively that I did. There is a good bit of wear on the 3-4 clutch pack but this being the first trans I've opened up and looked at I'm not sure what's normal. I ordered a rebuild kit so I will compare the new clutches to the old ones. The seals on the pistons look OK and the kit should have new ones.

I'm gonna take the pump apart also and see what it looks like.

Before I removed the trans I noticed it was leaking in the front somewhere and running down the bell housing. So apparently after I changed the fluid it blew a seal.

Since the trans was working but had a buck/shudder I consider this my failure. I didn't find anything that I can say for sure "this is what caused it".

I am still in investigation mode though, if I find anything I will update.


Great question BTW.

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so far it hasnt been all that hard has it? Just time consuming. My wifes van had a shudder and it turned out to be the wrong fluid!

Yes your right it has not been all that hard, just time consuming. I am starting to understand how it works, it's a good learning experience.

I'll be updating as I go.

Thanks for your help.

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You may know already but you`ll need a new gasket to mount the transfer case to trans also . dealer item, will need VIN number

I knew I needed the gasket but didn't know it was a dealer item. Thanks

Do you remember what rebuild kit you used?

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sorry cant think of it ,but if I remember I`ll let you know

I think I found my failure.
 

So I am starting to put this thing back together. I get to the input housing and load all the clutch packs. To test the operation of the pistons you apply air in the feed holes in the shaft. When I applied air to this hole (3-4 clutch pack) the piston moves and the clutches engage but there is air blowing past the orifice cup plug in the housing, It's the hole in the housing to the right of my hand. I don't think there should air leaking past that cup plug, am I wrong?

Input housing
https://blazerforum.com/forum/attach...ine=1436633881

Air testing.
https://blazerforum.com/forum/attach...ine=1436633881

Ah so I am wrong, and I just watched that video too.

Thank you so much.

On with the build.

I'm about to do the same thing. What kit did you end up getting?

There's a lot of seals in that kit, I don't know how I am going to use them all

I am following the book, it's pretty thorough.


Attachment 30793

I like the way your doing this, taking your time. Its gonna
work fine when done

I am definitely gonna upgrade the "sun shell gear" while I'm in there.

Great idea, if it has not already been updated. Mine has a thrust bearing on the inside instead of the washer like the book shows. Threw me off for a bit. Not sure if it's the updated one or not but it's back in the case.

There really not that bad either, maybe add like $50 to the rebuild.

Thanks, I hit a snag today though, I cut a seal trying to install the reverse piston. Oh well, get some new ones and try again.

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:icon_lurk5: Well? Is it back in yet?

LOL no not yet, it's still in rebuild mode.

There's some good video's and pics out there already so I have not been posting pics and progress.

I will say the most challenging part of the rebuild so far has been seating the lip seals without damaging them.

So the rebuild is almost done, then I get to put it back in and see if it works.

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it will work. re assembly is always easier also.

:icon_lurk5:

Update: trans rebuild is done, ready for installation.
 

This worked really well for re-sizing those white square cut seals. You move the zip ties up and get one more click on it then work it down over the seal, this squeezes it back tight in the grove.

https://blazerforum.com/forum/attach...ine=1438908886


These are all the parts/seals/filters that were taken out. I replaced everything I could find in the kit, except for some of the steel plates.

https://blazerforum.com/forum/attach...ine=1438908886

All done and ready for the pan.


https://blazerforum.com/forum/attach...ine=1438908886

A few helpful tips I found.
 

With just what I had laying around, a spring compressor.

https://blazerforum.com/forum/attach...ine=1438909712

I also used a drill press for a spring compressor.

Notice the feeler gauges on the bench. I used these to work the lip seal into the bore. You really need to take your time with that.

For the pump alignment I used a hose clamp, actually 2 hose clamps 5' long.


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nice job! Took me about an hour and a half to get that lip seal in. Every time I almost had it the piston would tilt and I'd have to start over. Do you have a parts washer? Everything looks so clean!

Are you referring to the reverse input clutch piston? Trying to get it into the reverse input drum? Yea I'm a little worried about that one, if reverse feels weak, or if I have no reverse I'll know why. I had the same problem, almost had it then it got crooked.

No parts washer yet. 3 gallons of kerosene and a drain pan and waste oil container from Wal-Mart. Most of the parts I washed in kero then hosed off and blew dry with compressed air. 1 box of gloves and a roll of shop towels. I tried to keep the work area as clean as possible. I did the work in my basement which is climate controlled.


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