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HOT AIR BALLOON OWNER
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Discussion Starter · #1 ·
This will be of some help:



1. Slow, slipping or no reverse: low/reverse clutches are worn out, fluid leak in the reverse apply circuit, or broken sun shell. It is possible to remedy a fluid problem by removing the check ball from its cage in the case in the rear of the trans may help (must remove valve body), or adding a high-viscosity additive such as Lucas Transmission additive or other seal restorer product.

2. No 3rd or 4th gear: 3-4/direct clutches are worn out. Remove & Replace.

3. Sudden grinding noise with no prior warning primarily in 2nd gear, behavior in reverse may be abnormal; sun shell is fractured. R&R. Try not to run or drive or further damage could result.

4. No 2nd or 4th gear. 2-4 band is slipping. Servo seals may be damaged (can be fixed without removing trans. Otherwise, 2-4 band is worn out. R&R.

5. Trans shifts into gear harshly, 3rd gear starts, manual 2nd available but no 1st, no 4th, and no TCC lockup: No power to transmission, or trans is in limp-home mode. Check wiring, and make sure transmission electrical connector is plugged in. Easy fix.

6. No 1st or 4th available: shift A solenoid failed. Easy fix in the pan.

7. No 2nd or 3rd available: shift B solenoid failed: Easy fix in the pan.

8. No TCC lockup: Brake pedal switches improperly adjusted (always on), TCC solenoid failed (easy fix in the pan), TCC clutch worn out (must remove trans and replace TC).

9. TCC always locked: TCC apply solenoid circuit shorted to ground, TCC solenoid blockage (easy fix in pan), or TC broken (must remove trans and replace TC).

10. 1-2 Shift shudder at WOT; delayed or abnormal 1-2 shift: 1-2 accumulator piston cracked or stuck cocked in the bore. Easy fix in the pan.

11. Horrible noise in 4th and feels like the brakes are on: overrun clutches are applying due to a cracked or leaking forward piston. Overrun clutches will be worn out after 30 seconds of this behavior. Can be safely driven in D. R&R.

12. Soft shifting, gradual performance degradation: Leaking boost valve; clogged EPC filter screen, leaky seals. Transgo kit fixes first two without removing trans. Seal restorer may fix last problem, but probably R&R.

13. No forward movement in OD or D, but L2, L1 and R work: Forward sprag is broken. R&R. Try not to run or drive the car or further damage could result.

14. Extremely harsh shifts from P or N, normal shifts at WOT: EPC (Electronic Pressure Control) solenoid failed. Easy fix in pan.

15. Loud bang, grinding sound, loss of all gears, and a binding driveshaft: snapped output shaft. R&R.

16. Trans seems noisy when moving in 1st and Reverse, noise goes away instantly if you shift to N: Reaction planetary is worn out due to high miles or insufficient lubrication. Not a critical failure, but not a good sign either. R&R.

17. No movement in any gear: pump failure, or total loss of fluid. R&R, or refill pan and find the leak. If out of fluid, avoid running the engine until the trans is refilled to avoid pump damage. To check for pump failure, check fluid level with the engine off, then start the engine and recheck fluid level. If level does not go down when engine is running, the pump is broken.

18. Trans does not upshift out of first, speedometer reads zero at all times: VSS failure. Easy fix on rear of transmission.

19. Transmission does not shift automatically, only manually. Swap in a known-good PCM, check wiring, check other sensors.

20. 1-2 shift is delayed and harsh, may not shift into OD: Check TPS for smooth and linear electrical response over the entire range of motion. If not, replace.
 
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disgusted
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Re: Is your 4L60E fucked/fucking up? Help within

seriously? my shitty shift from 1st-2nd could be a quick fix, either #10 or #12? throw in a corvette servo and I'm good to go. if that was so, it'd be amazing.

sticky x2
 

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Re: Is your 4L60E fucked/fucking up? Help within

I know I don't post much on here but I am having trouble with issue number one. I have an 03 tahoe and reverse seems like its binding up. If I back in a parking spot when the truck is warm it's not that bad, but on the other hand when it's cold out and I have to back out of a parking spot sometimes it feels like the damn drive shaft is in such a bind something going to break. Any ideas guys?
 

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Re: Is your 4L60E fucked/fucking up? Help within

:worship:

Sticky!
 

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TROLL REVOLT of 2012
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2,474 Posts
Re: Is your 4L60E fucked/fucking up? Help within

NICE INFORMATION


sticky.... my 2 gear is slipping :(
 

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Left Jizz
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Re: Is your 4L60E fucked/fucking up? Help within

Hmm. Any advice for intermittent TC lockup? Just locks/unlocks constantly, but only when warm. Cold it's fine.
I've been assuming it's the TC and waiting for it to burn up before I replace it, but it won't fail and it's been doing it for over a year now.
 

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TROLL REVOLT of 2012
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Re: Is your 4L60E fucked/fucking up? Help within

Hmm. Any advice for intermittent TC lockup? Just locks/unlocks constantly, but only when warm. Cold it's fine.
I've been assuming it's the TC and waiting for it to burn up before I replace it, but it won't fail and it's been doing it for over a year now.
Mine is doing that also.

Hopefully when i get my bb tune justin can tune the tc to be 100% open or closed.
 

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Re: Is your 4L60E fucked/fucking up? Help within

THIS is GMFS at its best. Thank you.:shake:
 

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Left Jizz
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Re: Is your 4L60E fucked/fucking up? Help within

Mine is doing that also.

Hopefully when i get my bb tune justin can tune the tc to be 100% open or closed.

IIRC he can tune yours, as yours is factory tuned to progressively engage for smoother operation.
In my Grand Prix it drives me fuckin nuts to watch the rpms stay the same and my speed goes up as it slowly locks up. Just lock it up and be done with it IMO.

However, mind should already just go to 100% locked with no in-between.

Also, mine has the diesel check valve that eliminates the electronics so I know mine isn't a computer issue. I can unplug the wiring harness from the trans and my TC still locks....or tries to.:crazy:
 

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TROLL REVOLT of 2012
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2,474 Posts
Re: Is your 4L60E fucked/fucking up? Help within

My transmission went out due to insufficient oil:

Before it went out, it would shift really soft you would hardly feel it shift, TC would keep unlocking and locking up, it would surge on curves, surging going up-hill, and when you would get on it would hit red line before it got a hold of the next shift.

Also if you have a Transmission temperature gauge, your needle should usually be sitting at 160 not towing. If you see it climb check your Oil.



-Miguel
 

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Re: Is your 4L60E fucked/fucking up? Help within

I'm having some issues with my '05 Sierra that I don't see or possibly just don't recognize from the list above.

When coming to a stop, I can feel the transmission downshifting through the gears which seems strange to me. Also when at low speeds if the transmission has to downshift (normal driving) it will issue a rather audible clunk.

Lastly sometimes when I'm taking off from a stoplight there seems to be another clunk, almost like the axle is moving or something.

Any of this sound familiar?
 

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Re: Is your 4L60E fucked/fucking up? Help within

Opinions? Any truth to this?

Transmission Fluid Evacuation Service
Back to Technical Service Bulletins
There has been a recent trend toward use of fluid evacuation systems in the
automatic transmission service industry in lieu of traditional transmission service
methods. These systems are used to pump the old fluid out of the transmission and
to refill with fresh fluid. This avoids dropping the pan and draining the unit which can
be time consuming and messy. The use of this method to replace the transmission
fluid is a clean, efficient, and safe way to remove hot oil from a transmission. The
problem, however, is that often times it is mistakenly thought that this represents
complete transmission service and that removal, and cleaning of the pan and
inspection and servicing of the filter are unnecessary.

Some people believe that all transmission filters are backflushed clean every time
the vehicle is turned off. This is a major misconception. Three-quarters of all
transmission filters today are not a simple screen, they are made of felt. A felt filter
CANNOT be backflushed. Felt holds dirt particles within tiny pores in the felt. It will
not wash out or flush out. If a felt filter becomes clogged it must be replaced.
Clogged filters restrict fluid flow, which lowers pressure to clutches and bands. This
can cause slippage and eventual burnout of the transmission.

Service manuals and textbooks on transmission service recommend that a
transmission filter be inspected and replaced, if necessary, as often as every 15,000
miles (24,140km), for severe service such as city driving, desert (hot dusty) driving,
extreme cold, frequent short trips, trailer towing, and delivery service. In normal
operating conditions the manuals recommend to inspect and replace the filter at
least every 30,000 miles (48,280km). Even the newer vehicles with 100,000 mile
(160,934km) drive train service warranties, the manufacturer recommends filter
replacement if the vehicle sees severe service conditions.

There have been an increasing number of instances surfacing recently regarding
transmission failures shortly after an evacuation service, without filter removal. At the
time of a fluid evacuation service, there is no way to know the condition of the filter
and how clogged it may be. The filters job is to collect and hold contaminants, (dirt,
metal filings, friction particles, etc.), and prevent these particles from causing
malfunction in such components as electronic force motors and solenoids. Today's
transmissions are far more susceptible to malfunctions caused by fine dirt
contamination. Without servicing the filter, there is no way to know if the filter is clean
of debris or nearing capacity. If the filter is nearing capacity, transmission failure may
not be far off. This is also a sign that there may be other internal problems in the
transmission. Recognizing these warning signs could eliminate major service later.
transmission. Recognizing these warning signs could eliminate major service later.
Most of the transmission failures after an evacuation service have occurred primarily
on relatively high mileage transmissions that have not been serviced in some time.
One reason for this is that the sludge and dirt buildup within the transmission will not
completely be removed during the service. When the new fluid (which has detergent
properties) is placed in the transmission, over days and weeks, the internal
components begin to wash the insides of the transmission.
This sludge does finally work loose and settles in the transmission filter, clogging it
up even further than it may have been before service. In these extreme cases, where
service has not been performed in some time, changing the filter may not completely
fix the problem. Some mechanics recommend a second service a few weeks after
the first, replacing the filter again, which may be partially clogged due to the cleaning
process in the transmission.

Even if the fluid evacuation method is desired to remove the used transmission fluid,
the pan should be removed also, and an inspection should be made of the pan
contents, fluid, and filter to determine the condition of the transmission. Aluminum
filings in the pan or iron filings on the pan magnet are signs of internal wear and may
give light to potential problems in the transmission. Transmission service is
performed for preventative maintenance. Evaluating the overall condition of the
transmission by removing the pan should be part of this preventative maintenance
also.
The Filter Manufacturers Council urges everyone to dispose of all used filters
properly.
 

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Re: Is your 4L60E fucked/fucking up? Help within

Any more info on #10, the 1-2 accumulator fix? Just want to know how to do it, whats involved.

Thanks
 

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HOT AIR BALLOON OWNER
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Discussion Starter · #19 ·
Re: Is your 4L60E fucked/fucking up? Help within

Any more info on #10, the 1-2 accumulator fix? Just want to know how to do it, whats involved.

Thanks


Involves replacing the piston in there. Drop the pan, pull filter, three bolts hold the accumulator in place... and there ya go.
 

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I am Tom Slick
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6,613 Posts
Re: Is your 4L60E fucked/fucking up? Help within

didnt see where it fit in there but here is the issue I am having:

~at first when the trans was shifting it sounded like when someone is driving a manual and keeps their foot on the gas and engages the clutch
~then it started revving really high before it would shift
~now i getting a problem from 1-2, it doesn't shift, I have to let off the gas for it to shift

then I tried to shift it manually from 1-2 and the computer still wouldnt let it shift

any help?
 
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