01ws666

Well had a track day planned tomorrow, just got a brand new set of the New Mickey Thompson ET streets mounted up after work today, after I picked the car up decided I'd hit it real quick from a 20 roll from manual 1st gear just to see how they hook on the street since I've been on street tires since november last year and miss the feeling of 1st or 2nd gear acceleration with no wheelspin and a yank PT3800 stall

And as soon as I do and go to hit 2nd she hits the rev limiter hard a few times I let off and coast to my street slowing down to make the corner and as I try to accel out of the corner car acts like its in neutral but gear selecter is in D drop it to 3rd... nothing there either, drop it to 2nd and I have 2nd, go to 1st and I have first also.....

So I went for a little drive to see whats going on and here's the run down;

Have reverse like normal no issues at all,
Have manual 1st like normal, no issues,
Have manual 2nd no issues there either,
Try to take off from a stop in 3rd or D and it just free rev's like i'm in neutral
If I drop below 10-15mph while in 3rd or d it free revs
if I go wot in D at a speed slow enough to drop to 2nd or 3rd it bangs the limiter until i let off then goes back into gear.
Manual 1st or 2nd hold good and was even able to go wot in manual 1st and grab 2nd and it worked and shifted good...
Dont know if the 2-3 shift would work wot yet, dont think it would there seems to be a small lag or hesitation now that there wasn't before.

Trans was built locally with lots of upgraded parts off the top of my head real quick;
Beast sunshell, sleeved input drum, billit overrun piston, borg warner HD input sprag, GM 5 pinion planetaries, alto clutch packs, z max 3-4 pack, billet servo's, hardened output shaft...

Any one have experience with the borg warner input sprag failing and causing the issue i'm having? Is there a better part for this? and is there something else that would cause the sprag to fail or is it just a weak link?

built408

iTrader: (10)

The sprag is gone. There isn't a better sprag then the BW one IMO. I have seen a few broken, most were due to WAY to firm shifts or TCC lockup. How were the shifts before?

performabuilt

iTrader: (25)

Now in the D3 and stopped in first gear the overun clutch is on and should bypass the sprag , What your describing sounds more like the low roller to me. In manual first and in cars with second gear start the low roller would be bypassed in 1-2 manual gears but not in D3 and OD positions.

01ws666

The shifts before were really firm, 1-2 was a strong jolt even at part throttle and MT chirping at full throttle... The 2-3 was just a quick snap. I had a superior 2nd - 4th billet servo in until last week my trans guy has been having an issue with 4th slipping under part throttle and eventually loosing 4th. last week he put the vett servo back in and that softened up the 1-2 shift a bit and 4th's been holding since putting it in. But with the billet servo yea 1-2 was pretty harsh...

Btw it also has a trans-go shift kit and he did something with the PWN or M managment that makes converter lock-up alot more feelable...

What do you mean by tcc lockup? you mean locking the converter durring shifts?

01ws666

I noticed you brought up the low rollers being the issue in a similar post when i did a search but it seemed to get dismissed and no one else brought it up So What are these "low rollers" and what part do they play exactly cuz I'm not familiar with them or how they work. That may be my issue cuz in both d3 and D the car acts like its in neutral.

BTW Is the car okay to limp around like this for a couple weeks or is there a good possibility I'm gonna F more **** up? Its not making any abnormal noises so far...

performabuilt

iTrader: (25)

The low roller set works very much like the input sprag, Except it only pertains to 1st gear in 3rd and od positions. Some cars in second to if they dont start in second when in manual second. When you pull down into manual 1 you turn on the low/reverse clutch set and bypass it then you can ussually shift through asll the other gears normally once you get going.
as for doing more damage its hard to say .

01ws666

Okay thanks it sounds like thats what probably broke then, So Is there an upgrade part for the low roller set?

performabuilt

iTrader: (25)

You can use the 4l65e set but its only a moderate stronger in fact we have only seen three fail in three years

01ws666

you've only seen 3 of the 60e or 65e low roller sets fail in 3 years? Thats not very many either way, guess my luck sucks huh lol.

Hey I've got a stupid question, how did i break something thats by-passed in L1 and L2 when I was in L1 when it broke?

performabuilt

iTrader: (25)

Now thats is a good question unless of course you dont hasve a transgo kit and the pcm comanded second then it would not matter

FLT

iTrader: (1)

Funny that you seem to always say the low roller in threads like this. Especially when you say that you have only seen three in the last three years. If the input sprag has failed then there is a good chance that what is happening with the OP's car is very possible. The reason I say this is because as we know the input sprag needs to be effective in order to move the car in both the OD and 3rd gear shifter position for 1st gear in a 4l60e. As mentioned bringing on the the low clutch or the band will allow manual 1st and second gears. No doubt that a low roller could be the culprit here but I would think that a bind in reverse would have happened in the roller has failed. I personally would be leaning torwards an input sprag failure. Now question for the OP, have you had a recent rear end failure? If so then a low roller is a very common trans failure after braking a rear end. I have also seen in many cases that the roller will fail and damage an input sprag at the same time. Also if you are having traction issues or wheel hop these failure can occur. Doing burnouts in manual low and getting traction in first causes these type of failures. The bottom line here is it's broke. Get it apart and fix it. If you continue to drive it you are just causing more damage with metal being sent through the system. In any case the unit will need to be fully disassembled and cleaned very well. I would also recommend getting the converter sent out to be cut and cleaned. Especially if there is metal in the trans. Good luck. Vince

performabuilt

iTrader: (25)

I will agree that both being damaged is very possible and would explain all the symptoms at once.
And yes the input sprag is needed for first gear in OD and D however the overun clutch is on in first gear in the D position and he says it wont move. However the low/reverse set is not on in 1st gear and D but is on in manual low 1 in first along with the overun clutch so thats why i think it to be the low roller. Now i do understand that is the low roller is seized it would lock the unit down in in higher gears but if the support is busted it would free wheel in both directions and you would get the sypmtoms described.
But as you said the point is something is broken and its gonna have to come down to be fixed.

FLT

iTrader: (1)

Wrong! The over run clutch is only on in a 4l60e in this case in manual 1st, 2nd and when the trans shifts to 3rd gear when in the D3 position. Also it is applied when the trans in manually shifted from OD to D3 for 3rd gear engine braking. This is commonly misinterpreted from the strategy of the 700r4. The two transmission use different strategies. This is why for the last 3 years we have been working/testing with a special valve for these valve bodies. This allows the over run clutch to be applied in the D3 position in all gears and helps to make the sprag live longer. We are currently installing this valve in all level 4 and up units. Making transmissions stronger and understanding how they work is what I call "stepping up to the plate" . That is the FLT way of building units. Giving the customer the most for your money and going strong! Good day. Vince

performabuilt

iTrader: (25)

My understanding is its on in 1st off in second and comes back on in 3rd in the D position. Much like you with the early TCC strategy on the converter regulator valve being stroked by the 2nd apply oil , I will have to look at some diagrams on this too.

tording99Z28

iTrader: (3)

This is the same issue I am having. I am pulling my trans on Monday to get it fixed.

FLT

iTrader: (1)

I think your understanding is incorrect on the over run clutch. Get a good hydramatic book and check it out. That is my bible! As for the TCC strategy a 4l60e has oil flowing through the LU solenoid in every gear range. This includes reverse, park and neutral. I have actually tested lockup in reverse on the axiline and it applies. The 700r4 on the other hand used second gear oil to accomplish this. Vince

performabuilt

iTrader: (25)

tHE 93 and 94 4l60e did require 2nd clutch oil to be there before lockup could happen. See diahrams below TCC signal valve circled. Now you are corect in that the 95 up PWM units uses the AFL circuit through the PWM solenoid then , by then called the ISO valve to accomplist this. So if PWM were eliminated in some way or the PWM solenoid energized yes you could make lockup in any position But not on those two years I was talking about orginally.

vince1.gif?t=1241899852

vince2.gif?t=1241900391

I will however conceed that it appears you are correct on the overun clutch I see where GM did indeed block the feed to it with the 2-3 valve when stroked. Odd they would do that. But I would imagine because of people complaining about the auto downshift abruptness in the D3 position just driving around.
Interesting however. Looks pretty easy to get around. Thanks for bringing that to my attention.
Frank

OP- Sorry for the high jack , Do however let us know what you do find. From the looks of it either and or both of us could be right.
Frank

01ws666

Lol just got home from work glad to see so much helpfull input on my thread i'm thinking we should start taking bets as to which of the two possible causes failed lol.
Wish I had gone with a built trans from either one of you now that I'm at where i'm at!
Will update this thread when I get her pulled appart.

BTW Vince I did have a rear end failure about a year ago which twisted my driveshaft like a soda can when It blew, I've also had an output shaft failure about a year and a half ago.

Well I'm off to the drag strip to go whatch all my buddies run their cars and not get to run mine LAME!

FLT

iTrader: (1)

01ws666 The rear end failure more than likely caused some of the damage we are discussing today. Sounds like your trans might be set up a little bit aggressive. You might want to have your builder tone it down a bit so you can reduce the risk of breaking hard parts.

Frank good point on the 93/94 4l60e system. I honestly do not look at my early books often seeing as that system was only used for two years. Next time I have a 93-94 on the dyno I will have to confirm this. I do believe it is possible because there were changes to the valve bodies when the pwm solenoid was introduced. Good point just not used in most of what we do. Vince

performabuilt

iTrader: (25)

Oddly we do quiet a few of these still of course we are also sponsors on the camaroz28 and LT-1 boards also which would explain that.
Have a great weekend Vince the weather super here for a change.