4L60E transmission slipping during lockup

[joejiz]

Hi everyone I'm new to the forum and thought I'd ask a question.

Info:
2005 Blazer 4.3L 4WD
128 000 KM
Tranny Fluid at correct mark on dipstick *no burnt smell*
Tranny Fluid Flush at 45K
Once a year converter slips in drive at lights up to 1800 rpm then grabs

Issue: TCC + Convertor Broken?

I drove the truck extensively and I can confirm going 70km/hr(40mph/hr) convert locks up and then it goes in and out of lockup over and over again, I can see the rpm drop 200 rpm, then go back up. I must be in the sweet spot of lock up. Memory serves me right this was 2000rpm highway.

Every now and then you hear the metal on metal grinding, not brakes.

When I go to 50 or 60 mph is when a scarry intermittent wobble drivetrain shutter will happen for like a full second, then go away and come back in like 5 seconds. This repeats itself.

I've had a tranny place say they see converter slippage and that I need a new converter. He went on to say that while tranny is out you may as well do full rebuild. Those cost of the rebuild gets close to the value of the truck in Canada.

I saw another post on her that says this can be fixed without replacing the converter and without removing the tranny?

http://api.viglink.com/api/click?fo...ion slipping during lockup - AnandTech Forums

 

[Jimzz]

I would drop the pan, clean, and replace the filter and fluid first. Its been over 60k KM so probably due for a filter change anyways.

Start simple and go from there.

 

[chucky2]

When they did the fluid exchange, did they use OE fluid or something else? Did they add any type of friction modifier?

 

[joejiz]

Hi,

If I go to a shop and tell them I'm experiencing this problem and then I SAY "well let's start with a full service on trans", maybe the see metal filings, maybe it looks just fine.

Maybe it works maybe it doesn't but what do they have to lose? If it doesn't fix it then I assume that's a waste of money because then they'll say "Well you told us to drop pan and do the job" and this work would of been done with a converter change/rebuild?

I'm a hobbyist so I don't have a garage to work in to drop trans. I've been quoted $3300 for rebuild and $1000 for new converter install. Truck is worth $5000 so gotta do my home work.

Here is receipt. I never had any slippage at lights until after this shop put the new fluid in. I ignored it since it happened so little and well this service was in 2008.

O wait weird I can't even upload a pic here.

Receipt says pan gasket, filter, Fluid, 80/90, shop supplies, psi additive = Total $74.50 CANADAIAN

Service tranny - $70
Server rear dif - $60
Change transfer case fluid - $15

total 245.85

 

[chucky2]

Hi,

If I go to a shop and tell them I'm experiencing this problem and then I SAY "well let's start with a full service on trans", maybe the see metal filings, maybe it looks just fine.

Maybe it works maybe it doesn't but what do they have to lose? If it doesn't fix it then I assume that's a waste of money because then they'll say "Well you told us to drop pan and do the job" and this work would of been done with a converter change/rebuild?

It's your vehicle and your money, so in the end the shop will do whatever you want them to do as long as you're paying them. If they drop the pan to do the filter change and the thing is completely full of chunks of metal/metal sand, don't bother getting the fluid changed, you're F'd, you need a new trans. If they drop the pan and it doesn't look too bad, then a new OE filter (that's, a filter made by the manufacturer of your vehicle) and, this is key, your manufacturers OE trans fluid for your trans, without additives, is a worthwhile try.

I'm a hobbyist so I don't have a garage to work in to drop trans. I've been quoted $3300 for rebuild and $1000 for new converter install. Truck is worth $5000 so gotta do my home work.

This seems high to me, but, it's been a very long time since I had to have a reman trans installed. You could take a chance on a junkyard pull, especially at a yard that will allow you to bring it back if it doesn't work. Sometimes you can find do it yourselfers that have a relationship with a yard that have such agreements setup like that. For example we got a junkyard trans that worked perfectly fine for $350 for our '92 Aerostar, plus another $350 for the guy to install it.

Here is receipt. I never had any slippage at lights until after this shop put the new fluid in. I ignored it since it happened so little and well this service was in 2008.

O wait weird I can't even upload a pic here.

Receipt says pan gasket, filter, Fluid, 80/90, shop supplies, psi additive = Total $74.50 CANADAIAN

Service tranny - $70
Server rear dif - $60
Change transfer case fluid - $15

total 245.85

And this is the problem with changing trans fluid at shops. First, for $70, I really doubt they did a t-tec change of all your transmission fluid. What they did is what is listed there: Drop the pan, replace the filter (who knows if what they used for a filter meets OE specs or not...probably but who knows), put in new pan gasket (or reuse your old one and charge you for a new one they never put in, who knows either way), and then put in some kind of fluid. What "psi additive" means is very suspect. It is very common for shops to get bulk fluid, and then use additives to 'bring it up to spec' for the vehicle it is being install into. This saves the shop money, and most customers are completely ignorant of what is going on to know why this is bad.

The only thing you want to use in your trans is OE fluid. That's it. The only exception to this is a fluid that has been certified ("meets" is not good enough, it must say certified) to meet the OE specs. Trans fluid is engineered by OEMs to have proper frictional characteristics for the transmission to shift properly and thus for long life due to correct operation (you should always change your trans fluid every 30-40k miles).

When these shops use their bulk fluid that doesn't natively have the proper frictional characteristics, and/or long life properties, anti-shudder, anti-foam, etc. etc., and then use an additive to 'bring it up' to OE level, they are basically long term potentially F'ing you. And their excuse, always, will be: "Well, we've never had a problem." HowTF do they know that? After 20-40-60k as the damage is slowly done, exactly how would they determine that all the vehicles they've contributed to F'ing up had problems? Even if they come back to them many thousands of miles later, the excuse will be: "Oh, it couldn't have been what we did, it's been fine for years/many thousands of miles now."

I'd start with a pan drop and filter change, asking them to pay attention to what's in the pan and what the filter looks like. Bring them an OE filter in the OE box and ask them to use that, even if they have to charge you for their shitty filter. Then have them t-tec flush the trans with OE fluid you have brought in, in sealed jugs. Don't flush 6 quarts which is what the shop above did for $70, flush however many quarts your trans takes. If they drop the pan and it looks like disaster, just do the new filter and have them top off the fluid with the OE stuff you brought for the flush, take the rest of the OE fluid back because you have bigger problems at that point a flush won't take care of.

Good luck.

 

[SparkyJJO]

It might be resulting from a fairly common issue on the 4L60E. The PWM valve bore for the torque converter lockup gets worn. When the trans is warmed up it can lose pressure on that valve, causing it to unlock a lot. Higher temps makes it worse.

I had it get really bad on the 4L60E in my old Camaro. Installing this combo kit fixed it:

http://www.ebay.com/itm/4L60E-4L65E...Parts_Accessories&hash=item51954b678c&vxp=mtr

That trans started to act up at around 115k miles (185,000 km), got really bad at around 145k miles (233,000 km), installed the kit and it has been perfect ever since and it is now at about 170k miles (273,000 km) I don't have that car but still have that trans in another car lol.

I've decided that any 4L60E I get will get this kit installed the first time I service the trans. I did that in my 02 Trailblazer at 119K miles (192,000 km) even though it had no symptoms yet, just to be safe. The truck now has 196k miles (315,000 km) and still runs flawlessly.

 

[joejiz]

Chucky2, thank you for detailed reply, I feel like I'm armed with good information!

God you are right, go figure the trans slippage at a light "once or twice a year" every year since they did that change.

I did hear one shop that took me on a diagnosis road test complain that the shop I took it too for that change (7bay) was horrible. So wouldn't surprise me they used the cheap fluid and filter. However you know how it goes

- "the one man shop tranny expert versus the 7 bay shop who's owner's name, which the reputation was built on, is no longer even working there!"

LOL

I see what you mean re: inspecting the pan. My focus should be finding a shop I trust so when it comes off should their be filings I can bite the bullet there and get it rebuilt. Of course asking for an estimate prior to this.

I've done this before with TH400 and there was no filings but it use to fly out of gear on a shift 2/10 times. The intermittent sprag was gone but that shop didn't know that by pulling the pan, (it was only rebuilt 9k prior when I bought car) they walked around the tranny than just quoted on the rebuild. I walked away, paid the $130, didn't trust him.

Found another shop to drive to and knew it had to come out, $1400 and they replaced all the stuff anyway even if it wasn't needed CUZ THATS WHAT YOU DO WHEN IT'S OUT.

The other replier to my post said that kit could be installed with a new servo without removing the tranny? My question is would a shop even know about this ebay part and servo and install it?

I'm gonna have to go for some more diagnosis test drives. Hopefully someone knows exactly what it is and isn't to chicken to recommend it without covering their ass and just saying "rebuild" it please.

Just a FYI the tranny works flawlessly everywhere else!!!

 

[chucky2]

I'm sure you can find a shop where if you bring them the part you can ask them to install it, just to see if it'll fix your issue. Maybe SparkyJJO can tell you how difficult it is to install it. If it can be easily done when the pan is dropped, you'll have to decide if in taking steps to troubleshoot/fix this, if you want to do one thing at a time or two. You can make an arguement for this either way, so pick whichever one you feel most comfortable with.

The important thing on the flush is a.) do a flush and pan drop with OE filter replacement, not just a pan drop, and b.) make sure to either use OE fluid or a fluid that is certified (not just "meets") to the OE standard your truck needs. You can calmly and politely explain to the shop that because you're troubleshooting, you want only one of these two fluids, preferably the OE. And I'd have a total price and price per quart figures in your head for these ahead of time when you walk in there, so you can figure out if the estimate they're giving you has been sky highed. Preferably I like taking my car to the stealership for trans flushes, after I've confirmed they use OE fluid (had a stealership use non-OE fluid once), and I let them know that I do not want any flush additives used before or after the flush.

Chuck

 

[joejiz]

Chuck, that makes perfect sense! Thank you very much for answering my questions and helping.

Sparky, do you know if that part on ebay requires the tranny to be dropped? Do you recall how many hours it took to install kit?

I'm thinking since the tranny shifts and does everything else perfectly, perhaps just a new converter, this kit and follow chuck's recommendation for oe fluid replacement with oe filter.

that would give it a real good blast of love, just not full love on a bench with a compressed air gun cleaning it out fully... lol

 

[joejiz]

I can't pm sparky until I have 25 + posts as I wanted to ask him how much labour/labor he paid to have the kit installed. Anyone know?

I notice these kits can be installed without removing the tranny from truck! YES!

I called the ebay company selling the kit and he said just make sure the shop installs all the components in the kit as you can't return any items.

 

[SparkyJJO]

Sorry forgot to check back.

Yes, you can do those with the tranny in the truck. I did mine with my vehicles up on a lift at my buddy's work. Can't tell you on labor as my buddy and I did it. I'm kind of a crazy DIY type guy lol, though my friend helped a lot and having him around helped boost confidence level in case something went wrong on my end.

 

[joejiz]

Wow, thanks I really appreciate getting back to me on this!!!

I did mean to ask what problem did you experience and after installing the kit did it fix it right off that bat? Also did you do a full fluid change at same time. I notice your tranny was at 180kish at the time?

I notice it says it stops shudder problem which is what I'm experiencing but I can't be sure the torque converter isn't broken. As well.

 

[joejiz]

Does anyone have any picture examples of too many metal pieces in bottom of pan?

Is 128K too risky for fluid exchange and all new OE fluid installed? I know I'm suppose to look for varnish in pan.

 

[SparkyJJO]

The problem I had was the torque converter not staying in lockup after the trans was warmed up. It would lock-unlock-lock-unlock-lock-unlock, or finally get stuck out of lockup, which hurt mpg and increased trans temps. It also started rev-slamming the 1-2 shift as it got worse.

Yes, I did a full fluid change while I had it apart. The old fluid wasn't burned or bad.

Usually, if the torque converter is broken it is BROKEN. Doesn't work at all, or makes horrible grinding crunching sounds. There isn't a lot to actually break in the converter, but when it does you know it.

Any actual pieces in the bottom of the pan is bad. Should never have pieces. The most you should have is a very fine metal powder (kinda sludgy feeling when wet with trans fluid) as that is typical clutch pack material wear.

No, 128km is definitely not too risky. No transmission actually ever will die because of a (proper) fluid change - a "backflush" or "reverse flush" is bad, never do that as it can knock stuff off the filter and force it into the trans. Forward flush is OK but always change the filter too. If a trans fluid change "kills" it, then the trans was about to blow anyway as the only stuff keeping it working (and barely) was the crud in the old fluid. Besides, most of the time trans fluid change intervals are about 100K miles (160km) so you're well under that, especially since you had a change at 45km.

 

[joejiz]

Thank you very much for your reply!

Well I certainly get a horrible grinding metal on metal type noise(1 second)when it's up in the 70km/hr every now and then and the shudder of course up in the 80-90km.

In your experience has a full fluid exchange with new oe filter every fixed a grinding noise too?

Any good tranny shop will hear that noise and SHOULD KNOW immediately it's the torque converter, right?

Am I way off with the diagnosis of : Fluid has lost it's friction ability thus something in converter is going dry causing metal on metal problem and subsequently when tcc is on even more load is applied requiring good fluid health thus more slip is seen by it shuddering?

That's what gets me.

Again thank you very much.

 

[SparkyJJO]

I've never had a grinding noise so can't say much on that...

 

[dtgoodwin]

I'm having the same issue on my 2002 TrailBlazer. It's at 189,000 miles currently. It's been doing this for about the past 30K miles. My symptoms are almost identical - slippage once in lockup if there's any load, but once past 65 MPH, it locks up fully.

I have a neighbor who used to work the "heavy line" at a Chevrolet dealership working extensively on this transmission. He agrees that it's likely the TCC valve bore being worn as that's a known issue, but also the lockup clutch is probably quite worn at this point. When I get the time (currently trying to move homes), I will get his help putting in a sleeve for the TCC valve and also replacing the torque converter.

FWIW, mine hasn't substantially degraded since I started noticing the slip. It is a little worse, but not a whole lot. My neighbor said that I'll likely just burn up the lockup clutch within the torque converter if I just let it go which shouldn't cause any problems unless it gets so hot that it breaks into pieces. At 189K miles, I'm not wanting to do a full rebuild. The rest of the transmission operation is just fine. It's had 50K fluid exchanges/filter and I've never seen much material on the plug. BTW, I use the method of disconnecting the cooler line at the transmission, attaching a hose to it, and running the engine at idle until it starts to get some air in the line. Immediately shut down the engine and refill with 4 quarts of fluid, repeating two times. After the third "drain", I drop the pan and replace the filter and add fluid to bring it up to full. This isn't a full flush, but it's pretty close replacing more fluid than the transmission contains. As you may know, these hold about 12 quarts between the torque converter and the transmission itself. You'll never get it all out without a rebuild - lucky to get about 1/3 with a pan drop.

Good luck!

 

[joejiz]

Thanks everyone.

I've learned that the PWM Valve plays a huge role in what's happening here - shudder. Either one could buy this part and get a shop to install this :
http://www.transmissionpartsusa.com/77754_04K_4L60E_transmission_TCC_valve_p/400-07775404k.htm

Which essentially puts the thing on steroids by reaming out bore and bigger more robust spring valve

or:

Buy the kit Sparky recommends http://www.ebay.com/itm/4L60E-4L65E...Parts_Accessories&vxp=mtr&hash=item51954b678c

That comes with a better designed PWM valve but no reaming and attacks the problem as a whole not just one area. [the plate, shift kit, pistons etc. ]

The corvette servo seems like a nice to have option on there too. So each of these parts all have different benefits and purposes to what they can/might solve.

Correct me if I'm wrong but all 3 should be SOP for any 4l60e tranny being rebuilt!

The big question still hanging out there is if line pressure is low and fluid doesn't hold could that make "some part" inside the torque converter make the grinding noise?

One would think a line pressure test while driving would at least prove the unit is applying the right pressure which should rule out PWM.

I keep hearing about a tcc clutch, is that a clutch inside the torque converter itself(pumpkin)

Thanks everyone for listening and everyone's advice. When it gets addressed I will be posting what the fix was and won't just let the thread die off.

 

[chucky2]

128k km is like 80k mi. Not too much for a trans flush but really should not have gone that long. 30k mi is a much better interval.

You can kill a trans that would have (likely) kept going if you do a trans flush on a unit that has lots of miles on the fluid. Examples of deaths I've seen are is someone has like 200k mi on their trans, never a flush done (so factory fluid), flushes, and then in 20k mi, it's toast. Why? The prevailing explanation is that, at some point, the fluid lost it's proper friction level along with the level of particles in it, and the clutches inside would slip to some degree (generally not noticable to the user) due to improper friction of the fluid. The slippage is mostly mitigated by the now compromised fluid having more crap in it and being less 'slick'. So the clutches, while not in the state they'd be in if the fluid had been changed every 30k mi, are still working somewhat normally because the crappy fluid is allowing them to.

Now someone goes and changes all that crappy fluid out, and nice fresh new fluid, with the proper friction modifiers are added, and no crap particles are in there. So what ends up happening is the clutches start slipping - they were compromised but the old fluid was making up for that. Now new fluid, no masking. Soon the clutches are glazed and burnt up from slipping far more than they were before. Trans toasted.

Some people have no problems, some people get new trans. Pick your risk.

Chuck

 

[joejiz]

Hi,

Fyi : 128,000 km = 79,536 Miles

I try and put myself in another person's shoes so I understand where they come from.

Perhaps if I take it from the tranny place's perspective.

I hear a grind, I see a slip in an out (200rpm drop) so I know something is wrong so do I tell the guy he needs a fluid exchange, new torque converter and it's fixed or do I just sell the full rebuild and then he doesn't come back for a long time?

I mean do the shops always get the free ticket if it fails shortly after on practically any repair not being a rebuild? - > " Well sir, we told you so!" < -

LOL

So my next steps are going for some test drives with some shops until I hear a consistent story that makes sense from several shops.

Then I'm going to go through my flow chart of troubleshooting. Can't upload it!

I think a pressure test is a good idea don't you?

Now that I'm armed WITH ALL THE INFO from you guys I can make sure I don't get screwed over!

Thank GOD for smart guys like you.

FLOW CHART TYPED IN:

DROP PAN - > MEDAL FILINGS FOUND

Quote for rebuild gathered prior
Includes R&R time and PARTS on invoice
Review online with forum
Rebuild should include shift kit and
other improvements that any normal tranny place would know + Install Cooler + Warranty
DROP PAN: ( not bad)
Shop should say:
&#8220; full fluid exchange &#8220; w/ OE
&#8220; new torque converter &#8220;
&#8220; anything else they think INSERT HERE &#8220;
I say install:
Ebay powertrain kit
Corvette solenoid + hope for the best

 

[joejiz]

Hi guys just an update, I haven't had a chance to take it to shops yet . Hoping to do this soon. I'd like to find the ebay link that has the 3 kits in it locally and bring it to them so I don't have to import them from usa. can't see why I need too to that...a kit is a kit.

 

[silicon]

The problem I had was the torque converter not staying in lockup after the trans was warmed up. It would lock-unlock-lock-unlock-lock-unlock, or finally get stuck out of lockup, which hurt mpg and increased trans temps. It also started rev-slamming the 1-2 shift as it got worse.

Yes, I did a full fluid change while I had it apart. The old fluid wasn't burned or bad.

Usually, if the torque converter is broken it is BROKEN. Doesn't work at all, or makes horrible grinding crunching sounds. There isn't a lot to actually break in the converter, but when it does you know it.

Any actual pieces in the bottom of the pan is bad. Should never have pieces. The most you should have is a very fine metal powder (kinda sludgy feeling when wet with trans fluid) as that is typical clutch pack material wear.

No, 128km is definitely not too risky. No transmission actually ever will die because of a (proper) fluid change - a "backflush" or "reverse flush" is bad, never do that as it can knock stuff off the filter and force it into the trans. Forward flush is OK but always change the filter too. If a trans fluid change "kills" it, then the trans was about to blow anyway as the only stuff keeping it working (and barely) was the crud in the old fluid. Besides, most of the time trans fluid change intervals are about 100K miles (160km) so you're well under that, especially since you had a change at 45km.

a good transmission shop should know hot to do a flush IMHO. The customer should not need to educate them on how to do this. Also they should have access to TSB's for all transmissions and be able to use them. Anything other than this means you are in the wrong shop. JMHO

 

[chucky2]

Yes, they'll know how to do a flush, but, will they flush with the number of quarts of fluid in the system to at least approach doing a full flush, or, will they do something like 6 or 7 quarts out of a 14 quart system? And then as I pointed out earlier, will they be flushing with a OE certified spec fluid or one that either is 'brought up to spec' with an additive and/or one that is compatible/covers/other ambiguous non-OE certified term?

It's sad to say, you just cannot trust shops. You can't even ask, 'Will you use an OE certified fluid?', because they may just lie to you. What you need to do is ask, Exactly what fluid will you be using in my trans flush? And then you have to hope they're not making it up and will actually use it. This is why I like just going to a stealership to have them do the flush, and I still confirm with them they'll be using (in my case I have a Ford so Motorcraft) OE brand fluid, and no additive.

Don't like them take shortcuts and/or risk with a multi-thousand dollar piece of equipment in your ride that you're on the hook for replacing.

 

[joejiz]

Couldn't agree more, thanks everyone. If it wasn't for the stupid grinding noise I would just get a good shop to do the full flush and install corvette servo and ebay kit and be there for when the shop does the work.

If I do that route and it fixes shutter but still grinds obviously it's torque converter??? Again the vehicle shifts flawlessly and goes into all gears just perfect right now.

Real dumb question, I could try dropping the pan myself, contain all the fluid and then drop the pan, take pictures and then install all the old fluid back in if there is filings. I mean who cares at that point? Then I have to find a shop for rebuild no matter what.

Thanks again.

 

[chucky2]

You could do that, but, if you do, make sure you get under there first and wash the pan down good up to and including above the gasket and area above the gasket. When you're working under there, it's easy to dislodge dirt/debris and you don't need that going back in the unit if you refill with the existing fluid.