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2004 chevy trailblazer_lt
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Discussion Starter · #1 ·
I have an 04 4x4 TB with 198,000 miles with the 4.2l 6. The 3rd and 4th gear clutch pacs were burnt out. It was rebuilt but when I got it back 2nd gear is weak. It shift into 2nd at 20mph, 3rd at 45 mph and 4th at 48 mph. It takes alot of time for 2nd to get to 3rd. I manually started out in in L, 2nd, 3rd and D. Starting in second felt like a stick shift starting in 2nd or 3rd, I have an OBD code P0016. The engine starts and runs great. The throttle body was cleaned. There is also transmission fluid dripping near the driverside door. I am trying to decide if its time to give up on it. Thanks in advance for any help.
 

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'05 TB 4.2 EXT
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It ain't the relays --- that's a false flag.

Either the 2/4 band wasn't replaced or a new one was put in on a warped drum or the 2/4 servo ate out the case when it busted the cushion spring and now it's bypassing.

There could be a slug of other reasons why it's so --- but that is the normal cause ... well that, and if it was rebuilt in a sandbox or some slob's workbench.

FTR ---> putting the gearshift int 2nd/Intermediate will start the vehicle rolling in 2nd/Intermediate gear. This is posted in the owner's manual as a way of reducing wheelspin in ice and or snow at startup from a stop.

When you got it back with the weak 2nd gear --- did you take it back and say: "Fix it right this time"?

BTW --- 2nd and 4th uses that same 2/4 band (hence, it's why it's called the "2/4 band")

3rd/Direct clutchpack is the weak link in this transmission --- if it's being silly now, just wait till next month!
 

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'05 TB 4.2 EXT
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P0014 is the Cam Position Sensor is reporting bogus (or no-) numbers and the ECM doesn't like it. Hence, the code and/or light.
 

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2004 chevy trailblazer_lt
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Discussion Starter · #6 ·
P0014 is the Cam Position Sensor is reporting bogus (or no-) numbers and the ECM doesn't like it. Hence, the code and/or light.
I wasnt sure if the Pcode would affect the shifting. It sat a long time and code says change oil first. I did that and added cleaner not flush to the oil. I havent insured it for obvious reasons so I run it in my drive. I have $850 plus plates in it and I think it is time to give up. I could donate it to an organization but I cant itemize deductions on my taxes.
 

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'05 TB 4.2 EXT
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Wait a minute --- changing the oil is not the reason for the P-code --- it MIGHT be a code that pops up if the oil is too old, ultra thick or full of water from condensate that ran to the bottom of the pan because of --- well --- it can be from an inoperative PCV (very likely) tbecause no-one really understands how the PCV system works on these engines.

But --- leave that code for a while and chase the transmission problem first.
 

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2004 chevy trailblazer_lt
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Discussion Starter · #10 ·
--
Gawd yeah! Dat guy's amazing alright!

Where can we send him money?
Wait a minute --- changing the oil is not the reason for the P-code --- it MIGHT be a code that pops up if the oil is too old, ultra thick or full of water from condensate that ran to the bottom of the pan because of --- well --- it can be from an inoperative PCV (very likely) tbecause no-one really understands how the PCV system works on these engines.

But --- leave that code for a while and chase the transmission problem first.
Gawd yeah! Dat guy's amazing alright!

Where can we send him money?
As I understad it there is a PCV system but no valve?

OK. Back to my transmission. The guy used the 97-03 rebuild kit. My TB is a 2004 4.2l 4x4. Is that possibly my problem. He claimed nothing changed until 05.
 

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'05 TB 4.2 EXT
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--


As I understad it there is a PCV system but no valve?
That's what that guy's video is trying to say --- it IS but it doesn't HAVE.

OK. Back to my transmission. The guy used the 97-03 rebuild kit. My TB is a 2004 4.2l 4x4. Is that possibly my problem. He claimed nothing changed until 05.
I don't know what the transmission guy did to your unit -- I wasn't there ... but suffice to say it's not good.

Take it back and then take it back again until he gets it right.

Everybody gets one oops --- but totally draw the line at three.
 

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It ain't the relays --- that's a false flag.

Either the 2/4 band wasn't replaced or a new one was put in on a warped drum or the 2/4 servo ate out the case when it busted the cushion spring and now it's bypassing.

There could be a slug of other reasons why it's so --- but that is the normal cause ... well that, and if it was rebuilt in a sandbox or some slob's workbench.

FTR ---> putting the gearshift int 2nd/Intermediate will start the vehicle rolling in 2nd/Intermediate gear. This is posted in the owner's manual as a way of reducing wheelspin in ice and or snow at startup from a stop.

When you got it back with the weak 2nd gear --- did you take it back and say: "Fix it right this time"?

BTW --- 2nd and 4th uses that same 2/4 band (hence, it's why it's called the "2/4 band")

3rd/Direct clutchpack is the weak link in this transmission --- if it's being silly now, just wait till next month!
This is so important. One of my rebuilds was a slug.

Took too long to shift, among other issues.

Made him redo the whole thing. It was perfect till my cooler failed and let water in.

Mine had an issue where if the 2-3 shift happened up at 5k rpms it would have a super delayed shift. Almost slip like.

After he redid it it was a nice 1-2 and 2-3 crisp shift at 5k. Stayed firm all the way to 7k

only a little delay on the 3-4 at Wot but I never abuse that shift.
 

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2004 chevy trailblazer_lt
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Discussion Starter · #13 ·
That's what that guy's video is trying to say --- it IS but it doesn't HAVE.



I don't know what the transmission guy did to your unit -- I wasn't there ... but suffice to say it's not good.

Take it back and then take it back again until he gets it right.

Everybody gets one oops --- but totally draw the line at three.
Should the focus be on the servos or the accumulators?
 

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'05 TB 4.2 EXT
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Tear the whole thing down again and re-evaluate everything ---- it's the way to actually build a transmission.

Don't go looking for causes in just one area --- it's the sum of the parts that make the whole.
 

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'05 TB 4.2 EXT
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Let's talk about "shift firmness" OK?

IF you are running a bone-stock 4L60, it should have what we called "boulevard shifts" that are somewhat early by about 300 RPM and a gentle application of the TCC.

From there as a base-unit, we go up in firmness and shift timing ..... and remember that shift timing is very critical and represents maybe 70% of complaints or concerns by the customers when they get the unit back.

If shift timing is late, it tends to be --- er ... harsher, for the lack of a better word.
The engine will be closer to - or in the Power Band at that time and if can send more ponies to the unit and that results in some old person's bag of apples from the market scattering all over the floor.​
Old people don't like that --- well, SOME don't.​
If shift timing is early --- they happen so softly and get into OD so fasgt that there's no feel at all of it happening.
We call that "stacking" the shifts .... and it's bad for many reasons .....​
...........in that the front pump is being lazy and not producing much pressure or flow ...​
...........and the clutches and band(s) ... remember we're not just talking about 4Ls here .... their friction material is gently pushed into contact and they kinda spin or slip a whole lot more than they should ....​
...........and this will kill a transmission and waste a lot of fuel and can cause all sorts of other drivability problems.​
Low pressure shifts are a problem in a different area too -------------------
The annular sealing rings won't be pushed out to their sealing surfaces, and this causes blowby of the apply fluid especially around the stators and shafts that are required to not only establish concentric motion of the spinning parts in relationship to the slower --- or faster --- glanulus (hollow) shafts that carry fluid commands and lubrication to critical parts.​
Some annular rings are keylocked and some are scarf cut and some are solid needing an installation tool and a swage to reshape and reform them ....​
Then again ... some are just o-rings and they need a little pressure to seal themselves up too.​
I digress ........​
If some shifts are early and some are correct --- this might be to clearances being too tight in one or two areas ....
....... or accumulators being stuck in their bores ....
........the bores can be ruined with gouged material missing, promoting bypass leaks ....
....... and all thereby failing to modulate/moderate and affect the timing of the shift ...
....... causing application overlap and premature friction material wear ...
........................all kinds-a problems.

Most "firmness" problems are therefor a perception and may not be the correct reality .....
..... whereas "softness" IS ---> in and of itself ---> suicidal in a transmission.
It causes a lot of heat and creates a lot of unnecessary wear in that one friction unit has not fully released .....
.......when along has come the next friction unit too early, albeit it softly ---
.......but they fight each other for a few moments ..............
.......and if the convertor doesn't have the capacity to "eat that difference up" ---
--------------> or absorb the mismatch application/release ......
The clunk then becomes a complaint and it's back to the shop --- again.

Once a customer has had a failure like any of those....
..... especially if it happens more than once ----
..... they are on the lookout for even the tiniest "something" that they feel now ---
..... and YOU have a very hard time selling the job is now correct.
They don't believe you.

Me, as an 'old guy' .... I LIKE a healthy shift ---- one that can chirp the tires if I wanna!

Putting in a shift kit --- even a mild one, can cause a lot of communication errors and crossed-expectations.

Before I forget --- "Hanging control valves" can be a corrupting factor too, in that if they don't release - or they don't open or apply in a timely manner --- then things go rapidly wrong too.

When you diagnose and repair transmissions --- there are so many things to think of --- all the time --- or you won't fix it right, if at all!
 

· Registered
2004 chevy trailblazer_lt
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7 Posts
Discussion Starter · #16 ·
Let's talk about "shift firmness" OK?

IF you are running a bone-stock 4L60, it should have what we called "boulevard shifts" that are somewhat early by about 300 RPM and a gentle application of the TCC.

From there as a base-unit, we go up in firmness and shift timing ..... and remember that shift timing is very critical and represents maybe 70% of complaints or concerns by the customers when they get the unit back.

If shift timing is late, it tends to be --- er ... harsher, for the lack of a better word.
The engine will be closer to - or in the Power Band at that time and if can send more ponies to the unit and that results in some old person's bag of apples from the market scattering all over the floor.​
Old people don't like that --- well, SOME don't.​
If shift timing is early --- they happen so softly and get into OD so fasgt that there's no feel at all of it happening.
We call that "stacking" the shifts .... and it's bad for many reasons .....​
...........in that the front pump is being lazy and not producing much pressure or flow ...​
...........and the clutches and band(s) ... remember we're not just talking about 4Ls here .... their friction material is gently pushed into contact and they kinda spin or slip a whole lot more than they should ....​
...........and this will kill a transmission and waste a lot of fuel and can cause all sorts of other drivability problems.​
Low pressure shifts are a problem in a different area too -------------------
The annular sealing rings won't be pushed out to their sealing surfaces, and this causes blowby of the apply fluid especially around the stators and shafts that are required to not only establish concentric motion of the spinning parts in relationship to the slower --- or faster --- glanulus (hollow) shafts that carry fluid commands and lubrication to critical parts.​
Some annular rings are keylocked and some are scarf cut and some are solid needing an installation tool and a swage to reshape and reform them ....​
Then again ... some are just o-rings and they need a little pressure to seal themselves up too.​
I digress ........​
If some shifts are early and some are correct --- this might be to clearances being too tight in one or two areas ....
....... or accumulators being stuck in their bores ....
........the bores can be ruined with gouged material missing, promoting bypass leaks ....
....... and all thereby failing to modulate/moderate and affect the timing of the shift ...
....... causing application overlap and premature friction material wear ...
........................all kinds-a problems.

Most "firmness" problems are therefor a perception and may not be the correct reality .....
..... whereas "softness" IS ---> in and of itself ---> suicidal in a transmission.
It causes a lot of heat and creates a lot of unnecessary wear in that one friction unit has not fully released .....
.......when along has come the next friction unit too early, albeit it softly ---
.......but they fight each other for a few moments ..............
.......and if the convertor doesn't have the capacity to "eat that difference up" ---
--------------> or absorb the mismatch application/release ......
The clunk then becomes a complaint and it's back to the shop --- again.

Once a customer has had a failure like any of those....
..... especially if it happens more than once ----
..... they are on the lookout for even the tiniest "something" that they feel now ---
..... and YOU have a very hard time selling the job is now correct.
They don't believe you.

Me, as an 'old guy' .... I LIKE a healthy shift ---- one that can chirp the tires if I wanna!

Putting in a shift kit --- even a mild one, can cause a lot of communication errors and crossed-expectations.

Before I forget --- "Hanging control valves" can be a corrupting factor too, in that if they don't release - or they don't open or apply in a timely manner --- then things go rapidly wrong too.

When you diagnose and repair transmissions --- there are so many things to think of --- all the time --- or you won't fix it right, if at all!
Wow, that was alot to take in and I thank you. I havent decided if I am going to junk it or try to sell it as is. Asking the guy who did the rebuild to drop it and verify the job and test everything is not an option. I have $850 in it after a new battery. I dont know if I donate it to a charity or maybe Boy Scouts if they will sell it for scrap or fix it. Anyway thank you.
 

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'05 TB 4.2 EXT
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That's ungodly cheap. I have $2000 in mine and that's after a really good discount because the shop that did it here in Montana is an old buddy in the business from SoCal ... where we had competitive shops in different towns.

But an $800.00 sounds troublesome ....
 

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2003 chevy trailblazer_ls
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701 Posts
Wait a minute --- changing the oil is not the reason for the P-code --- it MIGHT be a code that pops up if the oil is too old, ultra thick or full of water from condensate that ran to the bottom of the pan because of --- well --- it can be from an inoperative PCV (very likely) tbecause no-one really understands how the PCV system works on these engines.

But --- leave that code for a while and chase the transmission problem first.
Changing to oil to get rid of a cam sensor code is one of the suggestions general motors tech will throw out there for you. Low oil causes it too if it's got VVT.
 

· Premium Member
'05 TB 4.2 EXT
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6,201 Posts
Changing to oil to get rid of a cam sensor code is one of the suggestions general motors tech will throw out there for you. Low oil causes it too if it's got VVT.
That's a Hail Mary and everyone knows it --- blame it on inferior oil and possibly a different brand of filter too while you're at it.

Dealerships generally suck big ones.

The VVT fails from condensate causing it to seize with rust. Yeah --- they need oil, but if the engine's not complaining with rattling rods, then there's more than enuff to keep the VVT working - (again a caveat: if it's not rusted).
 
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