Hemi TC -- Information to Consider

Mountainman · **Posted:** Fri Feb 09, 2018 6:56 pm

My new hemi converter from Florida TC felt the same, and we're no where near the torque limits for either, so I don't think it's the TC, but time will tell.
I like WW's idea about contacting suncoast, and my suncoast was robbed from one of my other jeeps, so it may be an early production :dizzy:

Mountainman · **Posted:** Fri Feb 09, 2018 7:02 pm

flash7210 wrote:

Mountainman wrote:

Well, there goes my TCM tune theory! I believe you are right WW, and another member said there's a spring that Goes in the front pump that increases the TC pressure. In fact my sonax booster kit came with one lone spring for the front pump. I really hope that I only have to drop the transmission one more time :furious:

I thought I could get away without any pump upgrades because it was the updated pump and a remanufactured unit. I should have listened to you all that were harping on the need for the transgo kit, because I believe that spring is included in that kit as well :banghead:

Check those transgo instructions again.
I believe a special tool was required to ream out the piston bore for that spring.
If you installed a updated pump, that issue should have already been corrected.

Thanks, the remanufactured transmission came with the updated pump, but it was probably built on a Friday afternoon because when I went to change the filter (suddenly got really bad drain-back)and found the blow by valve lying in the pan. Screwed it back in with new filters and that solved that problem :lol:

Mountainman · **Posted:** Fri Feb 09, 2018 7:11 pm

Here's a weird one that would probably tell an expert something. So, if I take off from a stop, the shudder is terrible from 2-3 and 3-4. But, if I have been traveling down the highway for miles in 3rd, and then shift to 4th, the shudder is much less! Like it's pumped up/higher pressure. I don't get it.
Edit: oh, sometimes when its "pumped up" it has zero shudder. That's what made me wonder about the software. I got this a few times as it got used to the line booster, but it learned it's way back to bad behavior.

Side note: the sonax line booster made the shudder slightly worse...

flash7210 · **Posted:** Fri Feb 09, 2018 7:21 pm

Mountainman wrote:

Here's a weird one that would probably tell an expert something. So, if I take off from a stop, the shudder is terrible from 2-3 and 3-4. But, if I have been traveling down the highway for miles in 3rd, and then shift to 4th, the shudder is much less! Like it's pumped up/higher pressure. I don't get it.
Edit: oh, sometimes when its "pumped up" it has zero shudder. That's what made me wonder about the software. I got this a few times as it got used to the line booster, but it learned it's way back to bad behavior.

Side note: the sonax line booster made the shudder slightly worse...

Speeds tell me more than what gear its in.
In 2nd and 3rd gears the TCC is not applied, therefore there should be no shudder.
Unless you have OD-off, then the TCC gets applied at about 38mph. And even then its very hard to get any shudder while locked in 3rd. You'd have to be pulling a heavy load up a steep hill and hard on the throttle to force shudder in 3rd.
4th gear (OD-on) can apply at about 35 but the TCC wont apply until 51 mph.
5th wont apply until about 61 mph and is where shudder is most common.
All the above is with a stock TCM.

Mountainman · **Posted:** Fri Feb 09, 2018 7:32 pm

flash7210 wrote:

Mountainman wrote:

Here's a weird one that would probably tell an expert something. So, if I take off from a stop, the shudder is terrible from 2-3 and 3-4. But, if I have been traveling down the highway for miles in 3rd, and then shift to 4th, the shudder is much less! Like it's pumped up/higher pressure. I don't get it.
Edit: oh, sometimes when its "pumped up" it has zero shudder. That's what made me wonder about the software. I got this a few times as it got used to the line booster, but it learned it's way back to bad behavior.

Side note: the sonax line booster made the shudder slightly worse...

Speeds tell me more than what gear its in.
In 2nd and 3rd gears the TCC is not applied, therefore there should be no shudder.
Unless you have OD-off, then the TCC gets applied at about 38mph. And even then its very hard to get any shudder while locked in 3rd. You'd have to be pulling a heavy load up a steep hill and hard on the throttle to force shudder in 3rd.
4th gear (OD-on) can apply at about 35 but the TCC wont apply until 51 mph.
All the above is with a stock TCM.

Hmm, I have the gde eco tuned TCM, and it's at the lockup at 35, and 50. I didn't have the shudder at 35 lockup with the hemi, but I only get that when it's early in the drive, maybe low temp. One more difference is that the previous owner programmed the ecu for 32" tires, and so I'm shifting at even lower rpms 225/75's. I'm soon to go to 245/75's, so maybe that will help a lot??? I've been scared to get the only place around with the tool, the dealership to set my tire size correctly, especially as they gave me the no we can't ,yes we can confidence. They have never touched any of my CRD's to date...

flash7210 · **Posted:** Fri Feb 09, 2018 7:42 pm

Mountainman wrote:

Hmm, I have the gde eco tuned TCM, and it's at the lockup at 35, and 50. I didn't have the shudder at 35 lockup with the hemi, but I only get that when it's early in the drive, maybe low temp. One more difference is that the previous owner programmed the ecu for 32" tires, and so I'm shifting at even lower rpms 225/75's. I'm soon to go to 245/75's, so maybe that will help a lot??? I've been scared to get the only place around with the tool, the dealership to set my tire size correctly, especially as they gave me the no we can't ,yes we can confidence. They have never touched any of my CRD's to date...

So, 4th gear + lock at 35mph?
I could definitely see shudder happening there.
How does it behave with OD-off?

I didn't think shifting was in any way related to programmed tire size. Thought the programming only effected speedo calibration.
However, a tuned TCM will definitely effect shift points.

I'm on 32's and my speedo is about 8% slow. IDK what tires it was programmed for.

Mountainman · **Posted:** Fri Feb 09, 2018 9:41 pm

flash7210 wrote:

Mountainman wrote:

Hmm, I have the gde eco tuned TCM, and it's at the lockup at 35, and 50. I didn't have the shudder at 35 lockup with the hemi, but I only get that when it's early in the drive, maybe low temp. One more difference is that the previous owner programmed the ecu for 32" tires, and so I'm shifting at even lower rpms 225/75's. I'm soon to go to 245/75's, so maybe that will help a lot??? I've been scared to get the only place around with the tool, the dealership to set my tire size correctly, especially as they gave me the no we can't ,yes we can confidence. They have never touched any of my CRD's to date...

So, 4th gear + lock at 35mph?
I could definitely see shudder happening there.
How does it behave with OD-off?

I didn't think shifting was in any way related to programmed tire size. Thought the programming only effected speedo calibration.
However, a tuned TCM will definitely effect shift points.

I'm on 32's and my speedo is about 8% slow. IDK what tires it was programmed for.

Yes on the 4th @ 35, but the shudder isn't bad there, maybe I'm just feeling a lugging vibration there, but soon after, about 42mph the shudder gets bad, and I have to accelerate extremely slowly to avoid destroying the TC.
But, am I confused... I made sure that was the 3rd upshift, but at 50 is the fourth (5th gear), and about 63 is the 5th shift, so I guess I don't remember how this contraption works. 5 speed with 2 3rds or something like that?
With the OD off, it felt like there was a little less shudder, but probably not. If I get a lot of momentum from a low speed I can rocket through the shift at 50 with no shudder. If I didn't have 8 million mods on this thing I'd swap back to a stock tune and give up, but I'm in way too deep to ever let this thing go!

Sent from my SM-S820L using Tapatalk

flash7210 · **Posted:** Fri Feb 09, 2018 9:55 pm

Mountainman wrote:

flash7210 wrote:

Mountainman wrote:

Hmm, I have the gde eco tuned TCM, and it's at the lockup at 35, and 50. I didn't have the shudder at 35 lockup with the hemi, but I only get that when it's early in the drive, maybe low temp. One more difference is that the previous owner programmed the ecu for 32" tires, and so I'm shifting at even lower rpms 225/75's. I'm soon to go to 245/75's, so maybe that will help a lot??? I've been scared to get the only place around with the tool, the dealership to set my tire size correctly, especially as they gave me the no we can't ,yes we can confidence. They have never touched any of my CRD's to date...

So, 4th gear + lock at 35mph?
I could definitely see shudder happening there.
How does it behave with OD-off?

I didn't think shifting was in any way related to programmed tire size. Thought the programming only effected speedo calibration.
However, a tuned TCM will definitely effect shift points.

I'm on 32's and my speedo is about 8% slow. IDK what tires it was programmed for.

Yes on the 4th @ 35, but the shudder isn't bad there, maybe I'm just feeling a lugging vibration there, but soon after, about 42mph the shudder gets bad, and I have to accelerate extremely slowly to avoid destroying the TC.
But, am I confused... I made sure that was the 3rd upshift, but at 50 is the fourth (5th gear), and about 63 is the 5th shift, so I guess I don't remember how this contraption works. 5 speed with 2 3rds or something like that?
With the OD off, it felt like there was a little less shudder, but probably not. If I get a lot of momentum from a low speed I can rocket through the shift at 50 with no shudder. If I didn't have 8 million mods on this thing I'd swap back to a stock tune and give up, but I'm in way too deep to ever let this thing go!

Sent from my SM-S820L using Tapatalk

The 545rfe is actually a six speed but only 5 are really used.
1st, 2nd, 2 prime, 3rd, 4th, 5th.
2 prime is a kickdown gear and never gets used.

IDK the exact shift points for the GDE trans tune.
But for a stock TCM:
2nd at 10mph
3rd at 20
4th at about 35 depending on throttle position
4th + lock at ~51
5th + lock at ~61

With OD-off, 3rd is the top gear and the TCC usually locks at about 38 mph.

GordnadoCRD · **Posted:** Sat Feb 10, 2018 3:08 am

flash7210 wrote:

IDK the exact shift points for the GDE trans tune.
But for a stock TCM: Stock with Hemi TC
2nd at 10mph Same
3rd at 20 Same
4th at about 35 depending on throttle position 38
4th + lock at ~51 ~55
5th + lock at ~61 65

With OD-off, 3rd is the top gear (same) and the TCC usually locks at about 38 mph. ~40

At the Hemi TCC lockup point with pedal floored, shudder begins, and is MASSIVE when it tries to lock up. It tries to effect an "upshift feel", but the RPM stays the same (edit: around 2200) and the vehicle accelerates more like being towed with a rubber band than a solid shift feel. It takes roughly 5-7 seconds for engine rpm to begin rising again with acceleration, (at around 80ish+ mph.) and shudder begins fading at roughly 100.
With less torque, the Hemi would not have this problem, and I suspect that a Diff Re-gear would help as well, even though it's on 30" tires. -basically stock-

flash7210 · **Posted:** Sat Feb 10, 2018 11:51 am

GordnadoCRD wrote:

flash7210 wrote:

IDK the exact shift points for the GDE trans tune.
But for a stock TCM: Stock with Hemi TC
2nd at 10mph Same
3rd at 20 Same
4th at about 35 depending on throttle position 38
4th + lock at ~51 ~55
5th + lock at ~61 65

With OD-off, 3rd is the top gear (same) and the TCC usually locks at about 38 mph. ~40

At the Hemi TCC lockup point with pedal floored, shudder begins, and is MASSIVE when it tries to lock up. It tries to effect an "upshift feel", but the RPM stays the same (edit: around 2200) and the vehicle accelerates more like being towed with a rubber band than a solid shift feel. It takes roughly 5-7 seconds for engine rpm to begin rising again with acceleration, (at around 80ish+ mph.) and shudder begins fading at roughly 100.
With less torque, the Hemi would not have this problem, and I suspect that a Diff Re-gear would help as well, even though it's on 30" tires. -basically stock-

Yeah, with the pedal floored I could totally see the TCC shuddering when applied.
(this is why drag racers prefer non-lockup torque converters)
I would think that the TCC apply would be delayed until you lift the throttle slightly. This must be a unfortunate feature of the TCM.

I would try lifting the throttle a bit at the TCC lockup point to allow full engagement, then get back on it to see if it holds.

Mountainman · **Posted:** Sat Feb 10, 2018 11:57 am

Yeah, the gde tune locks the TC at 35ish shift, but other than that its similar to stock. Regardless, I've seen the same story on 3 transmissions and 3 TC's. I might just break down and pay the transmission shop to do the front pump upgrades, as I'm tired of pulling the dang thing without a lift.

I would be really careful to drive around that shudder, as mine is massive also, and I've seen it destroy the TC and transmission pretty quickly (a customer of mine insisted on pushing through the shudder...)

GordnadoCRD · **Posted:** Sun Feb 11, 2018 4:19 am

Having figured out it's M.O., I'm staying well off it until I make further changes.

Not only so it will last until then, but for the possibility of having something in salable condition after I do.

Mountainman · **Posted:** Sun Feb 11, 2018 6:51 pm

GordnadoCRD wrote:

Having figured out it's M.O., I'm staying well off it until I make further changes.

Not only so it will last until then, but for the possibility of having something in salable condition after I do.

I'm going to buy a new front pump and have the pros install the transgo bits, and install it myself. I wouldn't give up as there are plenty of lifted and tuned CRD'S without or shudder problem.

Mountainman · **Posted:** Sun Feb 11, 2018 8:58 pm

Here's the thread about the valve. Looks like even a new pump could be a problem without a transgo or sonax upgrade.

viewtopic.php?f=5&t=53444&view=previous

GordnadoCRD · **Posted:** Mon Feb 12, 2018 2:26 am

I went to the Sonnax site, and they have pretty well explained that through the the TC Limit valve, it is hydraulic action that disengages, not engages, the lockup clutch in the converter. The problem is too much bypass, resulting in partial clutch lockup at idle / low engine speeds, which glazes / burns out the clutch. This is definitely NOT the problem I am having.

https://www.sonnax.com/parts/29-tc-limit-valve-kit

I talked to 2 different reman outfits, and both say they ALWAYS ream and install the oversize switch valve kit with the 545RFE, on the grounds that if they don't, it will probably be a boomerang. Sounds like a good reason to just put in a reman pump. It doesn't make sense to buy a set of single use reamer and jigs just to use them once.

AS far as the increased line pressure, they said it affects transmission shifts, in speed and firmness, but not the TCC.
TCC lockup ability is spring force, surface area, lining material, and fluid / condition, and, apparently, TCM programming, since the solenoid is PWM type as well.

Mountainman · **Posted:** Mon Feb 12, 2018 10:49 am

GordnadoCRD wrote:

I went to the Sonnax site, and they have pretty well explained that through the the TC Limit valve, it is hydraulic action that disengages, not engages, the lockup clutch in the converter. The problem is too much bypass, resulting in partial clutch lockup at idle / low engine speeds, which glazes / burns out the clutch. This is definitely NOT the problem I am having.

https://www.sonnax.com/parts/29-tc-limit-valve-kit

I talked to 2 different reman outfits, and both say they ALWAYS ream and install the oversize switch valve kit with the 545RFE, on the grounds that if they don't, it will probably be a boomerang. Sounds like a good reason to just put in a reman pump. It doesn't make sense to buy a set of single use reamer and jigs just to use them once.

AS far as the increased line pressure, they said it affects transmission shifts, in speed and firmness, but not the TCC.
TCC lockup ability is spring force, surface area, lining material, and fluid / condition, and, apparently, TCM programming, since the solenoid is PWM type as well.

Well, on that note I'll put a stock TCM in it and report back

joelukex4 · **Joined:** Thu Sep 29, 2011 4:54 pm **Posts:** 386

flash7210 wrote:

GordnadoCRD wrote:

flash7210 wrote:

IDK the exact shift points for the GDE trans tune.
But for a stock TCM: Stock with Hemi TC
2nd at 10mph Same
3rd at 20 Same
4th at about 35 depending on throttle position 38
4th + lock at ~51 ~55
5th + lock at ~61 65

With OD-off, 3rd is the top gear (same) and the TCC usually locks at about 38 mph. ~40

At the Hemi TCC lockup point with pedal floored, shudder begins, and is MASSIVE when it tries to lock up. It tries to effect an "upshift feel", but the RPM stays the same (edit: around 2200) and the vehicle accelerates more like being towed with a rubber band than a solid shift feel. It takes roughly 5-7 seconds for engine rpm to begin rising again with acceleration, (at around 80ish+ mph.) and shudder begins fading at roughly 100.
With less torque, the Hemi would not have this problem, and I suspect that a Diff Re-gear would help as well, even though it's on 30" tires. -basically stock-

Yeah, with the pedal floored I could totally see the TCC shuddering when applied.
(this is why drag racers prefer non-lockup torque converters)
I would think that the TCC apply would be delayed until you lift the throttle slightly. This must be a unfortunate feature of the TCM.

I would try lifting the throttle a bit at the TCC lockup point to allow full engagement, then get back on it to see if it holds.

Mine has 5th + lock at 57mph. Pre F37.
I only have shutter at 1700 - 1900 rpms with cruise on and accelerating up a hill. Makes sense as the pedal goes to the floor to maintain speed. if I take off the cruise & keep the pedal off the floor I can manage without shutter. This is with a stock TC.

phum · **Posted:** Mon Feb 12, 2018 10:28 pm

As an aside, would a remote trans oil cooler help with this situation. It seems to me that the factory cooler in the condenser is a oil heater when the AC. Is on

Mountainman · **Posted:** Mon Feb 12, 2018 10:47 pm

phum wrote:

As an aside, would a remote trans oil cooler help with this situation. It seems to me that the factory cooler in the condenser is a oil heater when the AC. Is on

Nope, I've towed loads up to 8,000 pounds in hot and cold weather with no real change in shudder, other than the weight made it a little worse.

flash7210 · **Posted:** Mon Feb 12, 2018 11:33 pm

joelukex4 wrote:

I only have shutter at 1700 - 1900 rpms with cruise on and accelerating up a hill. Makes sense as the pedal goes to the floor to maintain speed. if I take off the cruise & keep the pedal off the floor I can manage without shutter. This is with a stock TC.

Mine is the same way.

Hemi TC -- Information to Consider

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