Something bad happened - Sunshell?

[MichEnvoyGuy]

I KNEW it was going to be a bad day... I replaced my drivers side tie rod and everything that could go wrong did. My work light burnt out, put a new bulb in it and it burnt out right away. I couldnt find my grease gun. I packed another grease gun and couldnt get it to prime. Couldnt find the right tools. I shouldve known then....

Anyways, I get the tie rod on and go for a test drive. Im honestly congratulating myself that I got the toe set, what seemed to be perfect. I was celebrating a little too soon because I went to go pass a car going 20 under the speed limit, I dropped the gas 3/4 to the floor, started passing the lady then all of a sudden...

BOOOOOOOOOOOOMMMMMMMM!!!!!
<<the whole Bravada jerks>>
WHIRRRRRRRRRRRR GRINNNDDDDDDDD



THANKFULLY I was in my neighborhood, got the car home, when you put the Bravada in reverse with the foot on the brake (not moving), it makes a heck of a noise. Whirring/grinding LOUD. In neutral and park its fine... but in Drive, when you accelerate and get over 10mph, then it makes the same whirring/grinding noise as it does in reverse.

So many things come to mind. First off, is the sunshell. Its an early 2002 with 137k miles and when I changed the trans fluid the other day, it was brown. To my credit, I siphoned 4 quarts out of the dipstick, had planned on doing it subtly.

When you put the car in reverse, it makes this LOUD stripped gear whirring now

Does this sound like I blew the sunshell?

Edit: My wrenching buddies are going to love that fact that I bought the truck Tuesday, and by Sunday I have already blown the transmission!

 

[kawaholic]

Man that sucks. Unfortunately, I think your diagnosis is spot on...

 

[MichEnvoyGuy]

Man that sucks. Unfortunately, I think your diagnosis is spot on...

I figured as much...

Wouldnt you know it though - I had my 02 (early build as well) Envoy for EIGHT years...EIGHT! I towed a 10000lb boat to the boat launch a few times per year, tuned the PCM, beat the snot out of that truck and sold it with 16x,xxx on it. Never had 1 problem with the trans or sunshell. (I also changed the trans fluid/filter every 20k miles though)

Buy a 2002 Bravy, figure Ill have the same run of luck... own it 5 days, BLOW the transmission!

Im making humor out of it to hide that Im really bummed.

Ok so I can get it rebuilt at my Dads old shop. My Dad is 77 now and with his arthritis, doesnt rebuild transmissions anymore, otherwise it would be just parts cost.

-or-

I can buy a used low mileage (95k miles) transmission from a local salvage yard for $500 and do it myself.




Btw, if you've ever been driving when that sunshell cracks, or whatever happened, its seriously one HELLUVA ka-boom!! I was really surprised I had ANY forward propulsion after that. And the noise The noise is what really ties it all together...what a racket it makes!!

 

[kawaholic]

I figured as much...

Wouldnt you know it though - I had my 02 (early build as well) Envoy for EIGHT years...EIGHT! I towed a 10000lb boat to the boat launch a few times per year, tuned the PCM, beat the snot out of that truck and sold it with 16x,xxx on it. Never had 1 problem with the trans or sunshell. (I also changed the trans fluid/filter every 20k miles though)

Buy a 2002 Bravy, figure Ill have the same run of luck... own it 5 days, BLOW the transmission!

Im making humor out of it to hide that Im really bummed.

Ok so I can get it rebuilt at my Dads old shop. Hes 77 now and with his arthritis, doesnt rebuild transmissions anymore, bummer right?
-or-

I can buy a used low mileage (95k miles) transmission from a local salvage yard for $500 and do it myself.




Btw, if you've ever been driving when that sunshell cracks, or whatever happened, its seriously one HELLUVA ka-boom!! I was really surprised I had ANY forward propulsion after that. And the noise The noise is what really ties it all together...what a racket it makes!!

I'll bet it made some noise...LOL

Ha ha, I do the same thing when there's nothing else I can do. Try to find the humor in a difficult situation. It seems like you're taking it all in stride while preparing for the ribbing from your buddies.

If you've got a place to work on it, I say rebuild it yourself. It's not really hard. If you're mechanically inclined, methodical and can pay close attention to details you can do it. I just got done doing mine recently. NEVER been inside an automatic transmission. It was a little overwhelming at first but I made it through. It sounds like you're ahead of the game with your fathers experience to help you out if you get stuck.

The way I see it, you're talking about spending 500 bucks on a used unit that could very well crap out on you at any time. For another 500 bucks you could COMPLETELY rebuild yours, upgrade the "known issues" with the 4l60e transmissions and KNOW what you've got.

I got my kit from Dana at pro built automatics. 700R4 & 4L60E Automatic transmissions specialists - ProBuilt VERY thorough kit and it comes with a dvd which walks you through disassembly, parts inspection and reassembly.

This is the kit I went with,

4L60E Rebuild Kit Heavy Duty 1997 & Up :: 4L60E ---- 700R4L60E.com :: GM Rebuild Kits :: Pro-Built Automatics

The only other thing I needed for mine was the reverse input drum. He told me I could reuse my torque converter (b/c there was no metal in mine) but I couldn't bring myself to put the old converter in after doing all that work. I wanted to go with one of the one's he recommends but just couldn't afford it. I got a remanufactured one locally for 160 bucks. When it was all said and done, I was in for right at 1k for the kit, TC, reverse input drum and 12 quarts of fluid.

Honestly, looking back on it now, I think getting the transmission out and back in was harder than the rebuild.

HTH, Tom

 

[MichEnvoyGuy]

Any reason a 4l60e transmission from a 2008 Trailblazer wouldnt work in my 2002 Bravada?

Found one with 44k miles for $450!

 

[Sparky]

As long as it came out of one with the same engine size I don't think so (bellhousing is different I6 vs V8 I'm pretty sure). Also not sure what differences there may be on 4x4/AWD vs 2WD models due to the transfer case bolting up to it.

Nearly 186k miles on my 02, just lifted it, all good so far *fingers crossed*

 

[DJones]

I had my 02 Envoy for EIGHT years. Buy a 2002 Bravy, figure Ill have the same run of luck... own it 5 days, BLOW the transmission!

What's the difference in serial numbers?

 

[dfc739]

Any reason a 4l60e transmission from a 2008 Trailblazer wouldnt work in my 2002 Bravada?

Found one with 44k miles for $450!

They changed the electrical connection from two plugs to a single plug around the 2003/2004 model years. So unless you want to change out the neutral position switch, no.

 

[kawaholic]

Nice find!!! I think it'd work. Even if it was out of a v8 and the bell housing was different (not sure if it is or not) you SHOULD be able to bolt your bell housing to the new one. You'd need to verify the bell housing bolts on and that it has the same bolt pattern.

NOTE, the bell housing bolts require a special t-50 torx bit. IIRC, it's called an "improved t-50" , specially designed for gm bell housings and available from snap on, mac, matco, etc. I got mine from the local transmission parts supply house, I'm pretty sure you can find them online too. You NEED this bit to remove the bell housing, along with an impact gun. If you try to use a regular t-50, you WILL strip the bolts.

It's my understanding that the AWD transfer case is a dumbed down version of the 4x4 transfer case internally. Externally, I BELIEVE they are the same but IDK for sure. Hopefully someone else can chime in on this.

Paging roadie, roadie please come to the courtesy desk!!!

If the unit you're looking at is out of a 2WD, you could probably bolt up your original tail shaft housing but I'm pretty sure the output shaft is different. Changing the output shaft requires complete disassembly of the transmission.

Edit:

It looks like the electrical connections are different, I was wondering about that. Also, I just thought about the input shaft and torque converter. I'm pretty sure my input shaft is a 30 spline, I'd imagine the 08 would be the same. Not sure that would matter as long as you got the torque converter with the new trans but you'll need to figure out if the TC's are the same from 02 to 08.

 

[The_Roadie]

I know very, very little about transmissions. The NP126 (AWD) transfer case omits the low range internally compared to the NP226 (4WD). Externally, the encoder motor has only five wires in the harness, not seven, because the AWD encoder motor omits the brake interlock feature needed for safety on the 4WD system to prevent the encoder from being slammed into LO range while you're moving.

 

[MichEnvoyGuy]

So the only update I have is, today Im having it towed to my Dads friends trans shop.

I called and they of course agreed, sunshell.

 

[KrisE]

So the only update I have is, today Im having it towed to my Dads friends trans shop.

I called and they of course agreed, sunshell.

::big hugs:: I envy you for being so knowledgable and knowing people you can trust.

I had a yukon at 270K when I traded it in. At about 120K I payed some CraigsList crook I think about $2100.00 to fix my tranny because it wouldn't go into reverse til warmed up. They didn't fix it of course.

I chalked that up to being car dumb and maybe as well because I'm female. If i had the tools and the room in my garage, I'd be trying some of these fluid changes and fixes myself. This forum is awesome! I'm driving my local mechanic a little nuts with my semi-knowledgeable interface, but it's ok cuz I think he's just naturally a bit cranky anyway.

 

[kawaholic]

I know very, very little about transmissions. The NP126 (AWD) transfer case omits the low range internally compared to the NP226 (4WD). Externally, the encoder motor has only five wires in the harness, not seven, because the AWD encoder motor omits the brake interlock feature needed for safety on the 4WD system to prevent the encoder from being slammed into LO range while you're moving.

All the information I'm finding on the NP126 and NP226 suggests they use the same case, even though they function differently. Would you agree?

 

[kawaholic]

So the only update I have is, today Im having it towed to my Dads friends trans shop.

I called and they of course agreed, sunshell.

Have you done anymore research on the transmission you found?

 

[MichEnvoyGuy]

Have you done anymore research on the transmission you found?

Yeah I'm going to pass on it. Theres some wiring differences, I dont want to go there.

 

[ScarabEpic22]

All the information I'm finding on the NP126 and NP226 suggests they use the same case, even though they function differently. Would you agree?

Yes, AFAIK all 3 GMT360 transfer cases are the same externally just the internal components are different. Bill can chime in here, Ive looked at my 02 4WD and few 06,07,08 TBSSs and the xfer cases look the same.

 

[MichEnvoyGuy]

Well the Brokeada (haha) is at my Dads ol' trans shop as of 20 minutes ago.

The stupid tow guy started it to move it off the flatbed, and now its whirring & crunching really bad, even in park My Dad met me up there to check it out, he used to rebuild 700r4's day and night and 4l60e's... he said there is metal moving throughout the transmission and causing more damage

Wish me luck, updates to come.

 

[Jtyler77]

Well the Brokeada (haha) is at my Dads ol' trans shop as of 20 minutes ago.

The stupid tow guy started it to move it off the flatbed, and now its whirring & crunching really bad, even in park My Dad met me up there to check it out, he used to rebuild 700r4's day and night and 4l60e's... he said there is metal moving throughout the transmission and causing more damage

Wish me luck, updates to come.

Good luck man! Hopefully you get her up and reliable soon.

Have you read novajoe's thread about his trannsmission? Seems he got something built strong for a good price just recently. If I remember correctly it was like $1500 shipped.

 

[MichEnvoyGuy]

Update!

The Brokeada got towed in last night to the trans shop. Today my Dad helped pull it out, and they started tearing it down.

Add me to the blown up grenaded sunshell party!!

The clutches were burnt and warped (which I think verifies my overheating transmission theory), the sunshell was cracked and separated, and my band was shot. There was a few other parts that were messed up but I forget what Dad said. Sprags? Or something...

But all is well and for 6 bills, they are rebuilding the transmission, flushing the cooler and lines, reinstalling the transmission and giving me my truck back with all new upgraded internals :wootwoot: They didnt even let me ask, and said the only sunshell they install in those transmissions is "THE BEAST". I googled it, and it appears to have a great reputation.

I'm pretty much getting labor or parts or both at a big discount. My Dad said they "owe him a few trans rebuilds" - because my Dad used to do their "comeback" transmissions, when they were real busy.

Ill update tomorrow when I get the Brokeada back and officially rename it back to Bravada but first it has to earn that title!.

 

[gmcman]

That's freaking awesome. Very glad it's working out for you..now hopefully the motor is sound and at least the trans should last quite awhile.

From the getgo......I would absolutely install an aftermarket cooler, Tru-Cool is worth taking a look at but most of them work well.

 

[MichEnvoyGuy]

That's freaking awesome. Very glad it's working out for you..now hopefully the motor is sound

Come on man, dont jinx me....lol

 

[kawaholic]

GREAT NEWS!!!! Sounds like you've got the hook up. Definitely put in an auxiliary cooler. Heat is the ENEMY of these (or any) transmissions.

My kit didn't come with the beast, kinda wished it did after the fact but it did come with the new GM "heat treated" sun shell. When I took mine apart, the sun shell and the sun gear all looked fine, so I wasn't too worried about it. All the research I did on different forums and such kept referring Dana's kits were the way to go, so I trusted the fact that he wasn't pushing to go with the beast.

The original sprag has a single cage, the new sprag will have a dual cage. I THOUGHT I took a pic of mine but I guess not. I found these on the web.

and that goes inside here

Most of my parts were in pretty good shape. 3-4 clutches were toast and the reverse input drum didn't look too bad but it was out of spec and got replaced. If your band is toast, (mine actually looked pretty good) I'd imagine you'll be getting a new reverse input drum. This is what mine looked like.

I'm curious as to whether or not you had any metal in the pan, I'd think you did. If so, I'm wondering if they're going to put an external filter in one of the cooler lines. That was one thing that Dana had mentioned when I was picking his brain on the phone. He said if there was ANY metal in the pan, I NEEDED to go with an external filter because it's impossible to flush the metal out of the lines and the cooler. Luckily I had no metal and didn't have to worry about that.

Thanks for the updates. Hope all goes well and you get your wheels back quickly.

 

[MichEnvoyGuy]

Got the Bravy back yesterday! :wootwoot:

Kawaholic, you're right - my band was toasted and they replaced that drum. They showed me my forward and rear clutches and they were all burnt bad.

My sunshell splines stripped, valve body got rebuilt. The trans filter caught a bunch of little pieces of metal.

Im too tired to remember what else they told me right now, but the trans got a full rebuild and shifts great now!! The shifts feel a little different than what Im accustomed to, but then again, my Envoy had a PCM4L tune with #1 shift firmness so maybe I forgot what a stock shifting 4l60e feels like, lol

Im going to wait 7.5- 10k miles, then drop the the pan and clean the magnet/change the filter and fluid.

 

[kawaholic]

AWESOME!!!!

 

[TollKeeper]

When I had my Tranny replaced at the GM dealer, when I got it back, it felt like a diferent animal altogether. It took a month or 2 to get used to it.

Glad the Bravvy is back on the road! Now make sure you remove that trash can! (if you haven't already)

 

[MichEnvoyGuy]

When I had my Tranny replaced at the GM dealer, when I got it back, it felt like a diferent animal altogether. It took a month or 2 to get used to it.

Glad the Bravvy is back on the road! Now make sure you remove that trash can! (if you haven't already)

Yeah Im getting used to it, maybe Im not used to normal 4l60e shifts with our programming? Either way, it hasnt blown up again yet so Im happy

 

[MichEnvoyGuy]

Hey guys, just wanted to update this thread with pictures.

Its been a few weeks and the rebuilt transmission is still working great (knocking on wood after saying that!)

Anyways, heres some pictures of what came out of the trans:

Heres a picture of the VERY burnt up clutches. They were burnt before the sunshell failure. Im guessing the transmission was on its way out when I bought it, I just happened to be the one to get the bill:

Stripped Sunshell teeth:

Burnt band that was also shot:

 

[triz]

Reading this is making me nauseous. In the am when I drop it into reverse it feels different. Can't really describe the sound but a bit louder than I think it should. Almost like a whirr. When I put it in drive it goes away and occasionally I get a whir when driving off. I was going to post up a thread about it and I hope I am not thread jacking yours but it sounds a bit like your issue. Except mine has not blown yet.

I was going to change the fluid soon. The last time it was done around 60k by Chevy/GM. It has 125 on it now. 2003 4.2I6 4x4.

 

[Sparky]

A whir when cold and shifting can happen and it isn't necessarily a sign of bad things. Someone explained it to me a while ago and it made sense, but I don't recall the details. Mine didn't used to but on occasion when it is cold enough it will make a little whir noise when shifting for the first couple cold shifts. Started noticing it last winter, and I've put a bunch of miles on it since then. It stopped when it got warm, so we'll see if it does it again as it gets cold.

 

[NeilLTZ]

I was in my 2003 LT 4x4 driving about 30 minutes from home in the country. Made a grinding noise and that was it. Nothing. No forward or reverse gears. I was betting the pump broke as my fluid level didn't change running or not. Turns out the converter let go and sent material thru the pump which destroyed it. But prior to that metal went thru the whole trans and contaminated the solonoids and left metal everywhere. I removed the trans in my shop and dropped it off at the local trans shop for a rebuild. By the time they were done estimating it was gonna be $1505 using HD parts, Sonnex sunshell and other parts typically used in H3 and Vette transmissions. It was gonna be built right.

But at 130K miles the rest of the truck isn't worth much although it's in great shape. I found a 80K miles used 2004 trans with a 3 month warranty from a local large salvage yard. Was very clean inside and out. So I bought it for $600 which included a new reman ProKing converter. Installed it this past weekend taking my time and doing everything right. New rear u-joints, pan with drain plug, new input seal, t-case output seal etc etc. Works flawlessly. Never realized how bad my former transmission was performing.

Anyhoo... the Sonnex sunshell my local trans shop recommended was the "smart shell"...not the "beast". Supposedly a new better design with changes that eliminate the load off the center gear area versus just beefing up the area. I'm not too sure...but something along those lines.

Also...the 2003 trans uses a 7pin and 4 pin dual connectors on the PRNDL switch. In 04 they went with a single 11 pin. I just switched out mine and it works fine. The main harness pin outs are the same on the 2004 valve body so that plugs in. The difference is that after 2005 the transmissions had an additional input speed sensor on it...which is why a 2006 up trans wont work well, if at all, on a 2003. So...a 2003 can use a 2004 or 2005 transmission if you switch out the PRNDL switch (easy).

Not a bad job. Had mine up on 4 HD truck stands....so about 24" in the air higher than normal. Wrote down the entire job in 25 steps. Take youre time, be precise and plan for problems. Took about 10 hours for removal. And 16 for install. I'm slow. And like to clean things up as I go.

 

[NeilLTZ]

Usually the sunshell internal teeth will round off and eventually strip....or the metal around that area on the shell body will break and disconnect the shell body from the shaft. The 4L60E (65E, 70E) is probably the best version of a 4speed auto OD ever created for many reasons. But it does have some flaws which can be corrected to make it very, very stout and durable behind most any engine. Bad thing is those little flaws will steal your lunch money.

 

[AtlWrk]

A whir when cold and shifting can happen and it isn't necessarily a sign of bad things. Someone explained it to me a while ago and it made sense, but I don't recall the details. Mine didn't used to but on occasion when it is cold enough it will make a little whir noise when shifting for the first couple cold shifts. Started noticing it last winter, and I've put a bunch of miles on it since then. It stopped when it got warm, so we'll see if it does it again as it gets cold.

If it starts just prior to a shift the culprit is a defective filter. When the trans is anticipating a shift it shoots up the line pressure from 40-60psi to ~160+psi. When the fluid is particularly cold and you have a bad filter the pump has a hard time keeping up and you get an unsettling whirring sound during each shift. It only last for the first few minutes and won't come back until a cold soak (typically overnight). If that's what you're hearing you need a new filter--it's not a sign of imminent destruction like the OP saw. To be perfectly clear this noise only occurs while the shifts are occuring (2-3 seconds), not while steadily in gear just driving around.

Reading this is making me nauseous. In the am when I drop it into reverse it feels different. Can't really describe the sound but a bit louder than I think it should. Almost like a whirr. When I put it in drive it goes away and occasionally I get a whir when driving off. I was going to post up a thread about it and I hope I am not thread jacking yours but it sounds a bit like your issue. Except mine has not blown yet.

I was going to change the fluid soon. The last time it was done around 60k by Chevy/GM. It has 125 on it now. 2003 4.2I6 4x4.

Only thing I could say is that a sunshell failure is an all-or-nothing event like the OPs. If it's going to fail it does so catastrophically without warning.

 

[MichEnvoyGuy]

Only thing I could say is that a sunshell failure is an all-or-nothing event like the OPs. If it's going to fail it does so catastrophically without warning.

Theres a lot of truth in this statement...LOL.

When it went, it went BOOM & jolted the truck like you've never felt and heard come out of your truck before.

There was no noises beforehand, no cutesy whirring or fun ticking noises (I'd welcome those over what happened ANY day, lol). I was driving in a spirited manner, it shifted into second, and at the exact moment, it said peace out.

Now I know what people say when they explain when their transmission blew, if "felt like it fell out of the bottom of the car" because when it happened to me, I thought "for sure" something shot off somewhere, based on the noise(s) it made and was continuing to make!!

 

[triz]

Good deal. Thanks for holding my hand. Will continue with my fluid change.