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4T65E-HD Delayed engagement fix

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Old Sep 2, 2014 | 01:42 PM
  #21  
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Slip and catch is due to seals not holding pressure consistently and adequately. This is because the factory seals shrink with age and mileage.

I recommend you contact Dave @ Triple Edge Performance before increasing your line pressure, as you could accelerate your problem.
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Old Sep 4, 2014 | 07:51 PM
  #22  
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My 06 Impala LTZ had the occassional slip when stopped at a light and then accelerating. I added the transgo shift kit, but it still occurred occasionally. Next step was to pull the side cover and replace the pressure solenoid which is generally the problem and requires a bit of work to do. Instead of doing that I had Cartuning slightly increase the trans pressure and also shift times. Problem has never occurred since then. Been about 6000 miles or so and no more issues.
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Old Sep 9, 2014 | 11:00 AM
  #23  
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Originally Posted by supercatxr7
My 06 Impala LTZ had the occassional slip when stopped at a light and then accelerating. I added the transgo shift kit, but it still occurred occasionally. Next step was to pull the side cover and replace the pressure solenoid which is generally the problem and requires a bit of work to do. Instead of doing that I had Cartuning slightly increase the trans pressure and also shift times. Problem has never occurred since then. Been about 6000 miles or so and no more issues.
That is what I was thinking, a very slight increase in pressure.

Can it be tuned to only be increased at IDLE RPM and car speed is at 0mph?

Why did they increase shift times?

Can you tell me who you worked with over there? Did they give you a list of parameters they adjusted, and the before and after values?

Thank you!
Brian
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Old Sep 9, 2014 | 12:09 PM
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I believe the pressure gets increased across the board, not just idle. Increase shift times so there is less wear on the clutches. Do you have HP tuners?
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Old Sep 9, 2014 | 12:18 PM
  #25  
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I don't have HP tuners now but this would make me want to buy it. I'd love to fine tune it for just enough pressure to eliminate the slip, but as low as possible still.

So there's no separate pressure setting depending on speed? How about depending on what gear you're in?
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Old Sep 9, 2014 | 12:49 PM
  #26  
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Originally Posted by supercatxr7
I believe the pressure gets increased across the board, not just idle. Increase shift times so there is less wear on the clutches. Do you have HP tuners?

Those rims you got , do you know if they will fit the CTS brembo's ?
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Old Sep 10, 2014 | 02:39 PM
  #27  
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Not sure...they are 18x7 impala wheels
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Old Sep 10, 2014 | 08:50 PM
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Originally Posted by bxd20
That is what I was thinking, a very slight increase in pressure.

Can it be tuned to only be increased at IDLE RPM and car speed is at 0mph?

Why did they increase shift times?

Can you tell me who you worked with over there? Did they give you a list of parameters they adjusted, and the before and after values?

Thank you!
Brian
There's nothing complicated you lower shift times so the wear and slip on the clutches is less.

.50 sec less till you like it.

You increase pressure for better holding of power and less wear

3-5% each time till it feels just firm enough.


In hptuners there are aldot of trans tables to adjust but the end result is awesome. Any competent tuner can get it done
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Old Sep 10, 2014 | 09:04 PM
  #29  
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Originally Posted by supercatxr7
Not sure...they are 18x7 impala wheels
Are they ss wheels? If so i know they wont clear the cts brembo's but i want them need a set to widen pm me if there ss wheels and how much u would want shipped
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Old Oct 16, 2014 | 09:13 AM
  #30  
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im glad you go it fixed been trying to figure this out for a while
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Old Jun 16, 2015 | 02:41 PM
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I'm still suffering with the random occasional slip-then-catch off line.

Boattail455 - is your transmission still working correctly off the line since you upgraded your magnets to pull more shavings out of the fluid? You are not the only person to find that upgrading their magnets fixed this issue, so I think I am going to give it a shot. It's cheap and easy compared to adding line pressure. You didn't use any kind of trans cleaning additive first, right? The other account I read, the owner put in 8 oz of Seafoam Trans cleaner before the pan drop.

I was considering buying HP Tuners and slightly bumping line pressures, but I couldn't get any clear help on the forums at hptuners.com. Wasn't clear to me whether I'd want to adjust the force motor current table slightly lower... or line pressure table slightly higher. Seems like people do either/both. And nobody could tell me how to limit the line pressure increase to 0mph at idle RPM. Because I never have a slip once moving, even slowly, and I'd rather not increase the pressure across the board if I don't HAVE TO. But If I have to, I probably would... like I said my questions were never answered there.

Thanks all!

Brian
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Old Jun 16, 2015 | 04:25 PM
  #32  
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Originally Posted by bxd20
I'm still suffering with the random occasional slip-then-catch off line.

Boattail455 - is your transmission still working correctly off the line since you upgraded your magnets to pull more shavings out of the fluid? You are not the only person to find that upgrading their magnets fixed this issue, so I think I am going to give it a shot. It's cheap and easy compared to adding line pressure. You didn't use any kind of trans cleaning additive first, right? The other account I read, the owner put in 8 oz of Seafoam Trans cleaner before the pan drop.

I was considering buying HP Tuners and slightly bumping line pressures, but I couldn't get any clear help on the forums at hptuners.com. Wasn't clear to me whether I'd want to adjust the force motor current table slightly lower... or line pressure table slightly higher. Seems like people do either/both. And nobody could tell me how to limit the line pressure increase to 0mph at idle RPM. Because I never have a slip once moving, even slowly, and I'd rather not increase the pressure across the board if I don't HAVE TO. But If I have to, I probably would... like I said my questions were never answered there.

Thanks all!

Brian
I did the Seafoam treatment. A little over 6k now, still no slip.

https://ls1tech.com/forums/ls4-perfo...rans-tune.html
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Old Jun 17, 2015 | 07:57 AM
  #33  
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Thanks rottonj, that's good to know.

In that thread I notice that one person suggested the Seafoam helped you by thickening things up, causing less blow-by on some seal. You corrected him in that Lucas is thick, but Seafoam is very thin, a cleaner.

On that train of thought, I just wanted to mention that I did give Lucas a shot. I put in about 1/3 of a bottle a year ago just to see if it happened more often, the same, or less. I found no difference, not even a slight reduction in how often it happens. So I personally no longer believe the issue is due to seal blow-by. I also don't really think its as simple as a worn forward band. My problems started around 60,000 miles and the car has been driven very very gently and I only have 200hp behind my 4T65-E.

At this point it's only a hunch, but I think the theory that the PCS gets contaminated due to being magnetic is a strong possibility. I have neodymium magnets ready to go. I am considering putting 4-5 of them in the bottom of the pan since I bought a 10 pack. I don't see how too many would be harmful? Along with fluid and filter again.
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Old Jun 17, 2015 | 09:06 AM
  #34  
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put them on outside of pan u don't need all them magnets in pan,the magnets will still pull the fragments to them,i got 2 on inside and 1 on outside of pan
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Old Jun 17, 2015 | 09:39 AM
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Originally Posted by bxd20
Thanks rottonj, that's good to know.

In that thread I notice that one person suggested the Seafoam helped you by thickening things up, causing less blow-by on some seal. You corrected him in that Lucas is thick, but Seafoam is very thin, a cleaner.

On that train of thought, I just wanted to mention that I did give Lucas a shot. I put in about 1/3 of a bottle a year ago just to see if it happened more often, the same, or less. I found no difference, not even a slight reduction in how often it happens. So I personally no longer believe the issue is due to seal blow-by. I also don't really think its as simple as a worn forward band. My problems started around 60,000 miles and the car has been driven very very gently and I only have 200hp behind my 4T65-E.

At this point it's only a hunch, but I think the theory that the PCS gets contaminated due to being magnetic is a strong possibility. I have neodymium magnets ready to go. I am considering putting 4-5 of them in the bottom of the pan since I bought a 10 pack. I don't see how too many would be harmful? Along with fluid and filter again.
The magnets should help. I'm curious why you only used 1/3 of the bottle of Lucas. Its a quart, used to replace a quart of transmission fluid. Possibly you may have noticed a difference if you had, or maybe not. The method I outlined in my post has worked well so far, its no cure all or fixed but It hasn't done that rev/clunk/slip **** that it was. Time will tell. Make sure you change the filter if you have not as well. Good luck.
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Old Jun 17, 2015 | 09:52 AM
  #36  
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Actually the bottle is 24 ounces, not a quart.

And I went back through my notes and I was wrong.... I didn't do 1/3 of a bottle, I did 1/2 of it, 12 ounces.

It's very thick and I left it in there for months, before I did my next pan drop. I was worried that all that extra viscosity wasn't good for the trans, especially if it didn't help my symptoms. I am pretty sure if it was going to thicken the fluid enough to stop some seal leak, I would have noticed at least a marginal improvement. At least a reduction in how often it occurs.

My test run was long enough I am 100% confident it did nothing at all. Which further backs my suspicion it's not a seal, nor is it a clutch/forward band. Not in MY case anyway, I am not speaking for all 4T65E owners obviously. It's quite possible we have similar symptoms with different causes.

I will attach a few magnets to the outside of my pan tonight and test for a couple weeks, then report back.

Thanks for your help and tips!!!
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Old Jun 17, 2015 | 10:31 AM
  #37  
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Originally Posted by bxd20
Actually the bottle is 24 ounces, not a quart.

And I went back through my notes and I was wrong.... I didn't do 1/3 of a bottle, I did 1/2 of it, 12 ounces.

It's very thick and I left it in there for months, before I did my next pan drop. I was worried that all that extra viscosity wasn't good for the trans, especially if it didn't help my symptoms. I am pretty sure if it was going to thicken the fluid enough to stop some seal leak, I would have noticed at least a marginal improvement. At least a reduction in how often it occurs.

My test run was long enough I am 100% confident it did nothing at all. Which further backs my suspicion it's not a seal, nor is it a clutch/forward band. Not in MY case anyway, I am not speaking for all 4T65E owners obviously. It's quite possible we have similar symptoms with different causes.

I will attach a few magnets to the outside of my pan tonight and test for a couple weeks, then report back.

Thanks for your help and tips!!!
No problem. You are right, its more than a quart. I added it first so I forgot that. Try the Seafoam treatment before changing the fluid and filter. I noticed a difference for the better in the way the transmission was shifting within 50 miles, it really was amazing as I was hopeful but not really expecting much.
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Old Jun 26, 2015 | 11:00 AM
  #38  
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Over 15000 miles now since bumping up pressure and shift times with hp tuners and not a single slip.

Originally Posted by rottonj
No problem. You are right, its more than a quart. I added it first so I forgot that. Try the Seafoam treatment before changing the fluid and filter. I noticed a difference for the better in the way the transmission was shifting within 50 miles, it really was amazing as I was hopeful but not really expecting much.
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Old Jun 26, 2015 | 12:05 PM
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That's fantastic. I don't have or know how to use something like HP tuners at all. Sounds like it really helped.
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Old Jun 26, 2015 | 09:20 PM
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nice super thats awesome
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