Jump to content

Recommended Posts

Posted

I've been in the repair business for the past 7 years, including almost 3 years as manager at a specialty transmission repair facility. I thought I would share a few of my experiences with the GM drivetrains.

 

The 4L60E transmission was one of our most repaired transmissions when I ran the transmission shop. The biggest problem I dealt with was the loss of 2nd, 4th, and reverse. Most people thought they needed a complete rebuild when they brought their truck in, and 9 times out of 10, it would only be the "reaction sun shell" which is a $30-40 part from Transtar (www.transtarindustries.com). One of the biggest causes of the sun shell gear breaking is somebody shifting into reverse while rolling forward or trying to rock out of a situation where they were stuck in snow or mud. It puts a lot of stress on a small gear, and it can either strip out or break. You should always stop completely before shifting from drive to reverse (and vice versa). A reaction sun gear replacement should cost under $1000 including labor. The transmission must be removed to replace it.

 

One of the other problems that I found on the 4L60E transmission was overheating from towing. If you tow, you should definitely consider getting a Hayden(or comparable) transmission cooler. Your torque converter takes a huge amount of abuse when you're towing and also put out a large amount of heat. If you drive hard, this should be one of your first modifications to the truck. If you overheat a transmission bad enough, you most definitely will be rebuilding that transmission and torque converter. Expect a $1500 to 2000 bill. Possibly more if you drive it until it stops.

 

Another common problem I found on the 4L60E transmission was the solenoids going bad. There's no rhyme or reason as to why they go bad, but they do. The Electronic pressure solenoid (EPC) was the most common, and can cause slipping, overheating, and a check engine light. The cost to repair the solenoids was usually under $500. Always replace all the solenoids, never just one.

 

Typically, during any type of service where the transmission pan needs to be removed, the filter should be changed.

 

The last common problem I found on the 4L60E transmissions was a boost valve leaking internally in the valve body. The boost valve would bleed off pressure that is needed to properly engage the clutches and the torque converter. The fix is a "boost valve boring kit" that reams out the valve bore, then you install a larger valve. This is another major cause of overheating within the transmission. Most of the time, a transmission cooler will not help this problem. Typically this is a $300-400 repair.

 

 

That's all I have off the top of my head, if anybody has any questions, feel free to ask, I still have my rebuilder's phone number if I get a questions I can't answer.

  • Like 1
Posted

Good info. Does tromping the gas from a stop put as much stress on the reaction sun gear as shifting between reverse and drive while moving?

Posted

Hell, I put mine in reverse doing 55 one time. It wasn't in there but a second and I'm still hoping I didn't screw something up. Has worked good sence then.

 

If you must know I was going for N and hit R.

 

 

Don

Posted (edited)

i think from now on i am going to make sure i completely stop before going in and out of reverse

 

btw what was the charge if you took the transmission out yourself and put it back in?

 

and would you recommend a filter change even though the fluid looks good and has a good smell? on a truck with 128,000 miles

Edited by 97SierraGMC
Posted

Good info. People with first hand knowledge of these things are always welcome. So far I have not experienced one single 4L60 failure (and I hope I don't) but I'll be the first to ask if I do.

 

Thanks.

Posted

I was talking to my local tranny shop about tranny temps when towing, noting that mine climbs to about 195-205 degrees when going up hill, and then leveling out about 186 during steady towing, and he told me that was acceptable. I then asked about synthetic oil in the tranny and would it help. He told me that he has not been sold on the synthetic oil as he has not seen enough evidence where it should be switched from dino oil. He also recommended a oil change yearly in the tranny if towing on a regular basis. I think that when I do take it in, I will most likely switch to Mobil syn oil in there. Any thoughts?

Posted

What's your opinion on the 4L70E? How does it compare to the 4L60E? How much more "Heavy Duty" is it? Does it experience these same issues?

 

Any opinions on the 4L70E would be appreciated.

 

Thanks!

Posted

Welcome Mike !

 

Where ya been ???

We've been waitin' years for a trans guy.

 

Now we need a:

motor guy

A/C guy

'puter guy

steering wheel guy

front end guy

brakes guy

rear end guy

tires guy

electrical guy

truck wash guy

body guy

paint guy

fuel system guy

 

Who else do we not have?

Posted
Welcome Mike !

 

Where ya been ???

We've been waitin' years for a trans guy.

 

Now we need a:

motor guy

A/C guy

'puter guy

steering wheel guy

front end guy

brakes guy

rear end guy

tires guy

electrical guy

truck wash guy

body guy

paint guy

fuel system guy

 

Who else do we not have?

 

 

 

 

uhhhhh a BEER GUY!!! :lol::lol::D:D:D

Posted
I have a 2008 NBS does it come with 4L60E ??

4L60E is the common trans unless you have the 6.0.

 

He's not saying that they are junk... just pointing out the things he has seen go wrong with them. Keep in mind, the tranny guy only sees the broken ones. This is not necessarily an indicator of the transmission's quality.

 

No panicking guys. The sky is NOT falling. :lol:

Posted

Mike, we really do appreciate the info and I am with you 100% on the heat and cooler. Did you use Hayden's stacked plate design coolers? This is what we attempt to sell and recommend from our stores. All info indicates they are much more efficient and flow better than the old style tube and fin coolers.

Posted
Welcome Mike !

 

Where ya been ???

We've been waitin' years for a trans guy.

 

Now we need a:

motor guy

A/C guy

'puter guy

steering wheel guy

front end guy

brakes guy

rear end guy

tires guy

electrical guy

truck wash guy

body guy

paint guy

fuel system guy

 

Who else do we not have?

 

 

 

 

uhhhhh a BEER GUY!!! :lol::lol::D:D:D

 

 

pizza and wings guy

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.4k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,759
    Total Members
    8,960
    Most Online
    DM22
    Newest Member
    DM22
    Joined
  • Who's Online   6 Members, 1 Anonymous, 1,658 Guests (See full list)


  • Latest Articles

  • Posts

    • Did have to make 1 modification because of the WeatherTech rear mud flaps and that was needing 3 longer screws than what came with the install package. 😄
    • Picked up the liners yesterday. Installed passenger side WITHOUT any modifications. All mounting holes lined up perfectly. Rain is interfering today with drivers side. Very Happy! Will add pics when finished
    • As a matter of amusement I’ll leave this conversation with this. Do you beat the government average fuel estimate? Statistics are a guide to me. Not a rule. Someone once said I have to have the last word. If true and possible may be. I’ll blame that on working in a family business.
    • That is a fair point, and I agree that trying to log “everything in the truck” would be the wrong direction.   There are a lot of modules and a lot of traffic. If the product became a full-truck datalogger, the amount of data would get huge very quickly, and most owners would never use it.   I think the first useful version would need to be narrow: - powertrain-side event evidence - selected high-value parameters - communication / voltage / reset events - pre/post event window - short report first, raw log only as backup   One distinction I should make is between active OBD/PID polling and passive bus capture. If you are polling PIDs through OBD, then yes: the more parameters you request, the lower the effective sample rate becomes, and you are adding diagnostic traffic to a vehicle that is already busy running itself. With passive CAN capture, the recorder is not asking all the modules for data. It is listening to traffic that is already on the bus. So it does not consume vehicle bus bandwidth in the same way that a scan tool polling hundreds of PIDs would. But your point still applies in a different way.   Even if passive capture does not add bus traffic, the recorder still has limits: - processing rate - storage rate - timestamp accuracy - decoder workload - event filtering - report size - user attention span   So the answer cannot be “log everything and let the user figure it out.” The product would need to store enough raw evidence to be useful, but only decode, graph, and present the important parts around the event.   A practical report should probably show: - what triggered the capture - how much pre/post data was preserved - which selected parameters changed - how those values compared to baseline - whether the same pattern happened before - whether any voltage, reset, bus-off, lost-message, or communication fault occurred - selected graphs around the event - raw data only as supporting evidence   So I agree with you. More data is not automatically better. The real product is the reduction from raw data into a useful event report.
    • That makes sense, and I agree with most of that.   I think the product would need both: 1. a default powertrain template, so it is useful out of the box; 2. user-selected priority parameters, so the owner or shop can choose what they want to see first.   Different users are going to care about different things. One owner may care about oil pressure and voltage. Another may care about misfire trend, AFM/DFM behavior, or U-codes. A shop may want communication events and repeatability first. Your baseline point is probably the most important one. Raw data is not very useful unless the report can show what normal looked like for that vehicle under similar conditions.   The way I would think about it is: - start with a basic known-good baseline - learn normal behavior for that specific vehicle over time - allow the event to be overlaid against baseline - show whether the event was a one-time spike or a repeatable pattern - provide a simple severity level, but with clear limits on what that severity means   For example, early severity could be something like: - Info: event captured, no obvious abnormal pattern - Watch: value moved outside baseline, but not repeated - Warning: repeatable abnormal pattern under similar conditions - Critical: communication loss, voltage drop, bus-off, reset, or severe repeated event   I would not want the first version to say “replace this part.” That would be overclaiming unless there is repair-confirmed data behind it. It would be more honest to say “this pattern deserves inspection.”   On the OBD port question, I think OBD absolutely has a role. OBD is probably the right place for: - DTCs - freeze frame - VIN - calibration information - normal scan-tool parameters - Mode 6 / enhanced diagnostic data if available The reason I am still looking at an ECM-side recorder is that the failure may happen before anyone connects a scan tool. If the owner plugs in a scanner after the event, the pre-event evidence may already be gone unless the ECU happened to save it. So I do not see this as “OBD versus ECM-side.” I see it more like: - ECM-side recorder: always armed, rolling buffer, event evidence - OBD/DLC companion: DTCs, freeze frame, VIN, calibration, normal scan data - phone/cloud: status, notes, upload, report generation, notifications   I agree that phone connection and push notifications would be useful. I just would not want the phone or cloud connection to be required for capture. The recorder should save the event locally even if the phone is not connected. The phone should help with event marking, download, notes, upload, alerts, and report viewing.   For a default GM V8 event report, would this list make sense? - RPM - calculated load / MAP - throttle position - vehicle speed - gear / torque converter state if available - coolant temperature - oil pressure - oil temperature if available - battery voltage - commanded AFM/DFM state if available - actual AFM/DFM state if available - misfire counters / roughness by cylinder if available - fuel trims - relevant U-codes / communication events - bus-off / lost periodic message / module reset / voltage drop events Which of those would you remove, and what would you add?
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...