- Thread starter
- #61
Wow. That seems like a very plausible answer. Probably.
Transmission
- Thread starter LC200JG
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- Thread starter
- #63
Nope no more noise.
@LC200JG, Did your mechanic actually remove the transmission to look at it, or disconnect the driveshaft or anything, or did he just listen on a road test or on the lift? I'm wondering if this was perhaps some sort of transfer case issue. The TC has a torsen limited slip differential in the center. If you disconnect the front driveshaft (like if you break a CV on a trail) then you have to lock the center diff or else the torsen LS will slip and send ~70% of the power to the front, but the power goes nowhere. I can't come up with an explanation as to why, but if somehow the LS was in some sort of slip/grip cycle maybe it would feel like the torque converter was slipping/surging?
- Thread starter
- #66
No he did not remove it. If the transfer case was actually messed up wouldn't it still be messed up? I wouldn't guess it would fix itself.
Not placing blame but just sharing my opinion. No fluids are lifetime and these are the lifeblood of your drivetrain. I chance diffs/transfer case every 15k, engine oil every 5k, PS and Trans every 30k. People say I’m wasting my money but I wonder if this was a contributing factor. Would be curious to see a video. The photos don’t look like any big deal of terrain.
- Thread starter
- #68
Sounds good to me. With 120k pretty sure it had never been changed.
I'd assume so. But then I'd assume the same thing with the transmission. WTF do I know?!? I'm just trying to think of any other reason you'd get driveline slippage. You're not resting your left foot on the clutch pedal are you
j/khas anyone explored torque converter locks to decrease trans temps?
I see a lot of aus folks using this and reporting drop in trans temps and better performance towning and low gear driving.
I see a lot of aus folks using this and reporting drop in trans temps and better performance towning and low gear driving.
The lockup kits only work with the diesel, doesn't work with the 5.7 petrol.
The TC will lock in 4th, 5th, and 6th in the '08-15 and I believe 5th through 8th in the 2016+. You are correct that locking it will significantly reduce transmission temps. You can't force it to lock but you can encourage it by downshifting to the highest gear you can practically maintain. i.e. if you're having trouble keeping the TC locked in 6th gear because of hills, then downshift to 5th and the TC will lock up and stay locked in 5th gear. If you leave the truck in "D" (6th) then 5th gear will NEVER lock up because for improved MPG the transmission ECU preference is to select the next higher gear unlocked instead of a lower gear with the TC locked.
Moby
GOLD Star
Agreed. What we really need is shift point conditioning. Downshifts need to be more aggressive at partial throttle and they need to hold that gear longer. I didn't find it to be as much of a problem with the 6 speed in my GX but more of an issue in the 8 speed in my 200. ECT doesn't make the nut.
I've been trying to wrap my mind around the torque converter locking strategy. Seemed strange that it won't lock in anything but 6th when in "D". Did some playing around on this and I've found my car to lockup in 5th or 6th readily when in "D". I'm pretty sure I use to feel it lockup in 4th too. EDIT: New observations of locking up 4th in "D" here.
So we see different behavior between your setup and mine. I wonder what a stock car would do. Anyone?
The difference in our cars is different tire diameters (34s vs 35s) and different diff ratios (4.88 vs 4.30), yours versus mine respectively. I wonder if this is a load computation difference that the ECU is seeing between engine rpm, wheel speed, and selected transmission ratio? If I had to guess, wheel diameter is not playing into this as the ECU is not referencing GPS speed. Just engine speed vs wheel speed, against the selected transmission ratio.
This may be an unintended consequence of re-gearing that it compromises the lockup logic of the torque converter?
You can see my transmission will lockup in "D" while in 5th, via the bolded blue horseshoe around the gear number.
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bloc
SILVER Star
I haven't yet played with importing 'Fusion dashboard layouts so will need to figure that out, and between that and a busy couple of weeks it may be after christmas before I can get to it, but I'm game. Though I am on 33s, I have stock gearing, for now.
afgman786
SILVER Star
When does your 200 shift out of 4th? I've noticed my 200 doesn't lock until I'm between 45-50mph. After locking around those speeds the slowest I've gotten before it unlocking was 40.. so wondering if you're getting out of 4th before the 45mph or so that it will lock up at?
It could be tire/gear (load, really) related. I have to admit I didn't really pay attention to lockup state until this year, and I've had oversize tires for several years now. We'd need someone with a stock 08-15 to use ODB Fusion and monitor for us so we have a baseline, I suppose.
I would reasonably assume the transmission might lock up in 4th or 5th if you're going slow enough that it doesn't want to go into 6th. I'm surprised to see you lock up in 5th at 51mph as I would think the truck would want to go to 6th gear at that point.
In fairness I normally don't monitor my lockup unless I'm towing, so the non-towing (unloaded) transmission lockup behavior may be different. I may be monitoring during the edges of how the ECU operates, not the normal case. Being that I'm typically towing it could also be the behavior is different with ECT PWR being enabled.
Funny enough, got her to lockup in 4th today on the morning commute.
Previously I was on a long road trip focused mostly on lockup with a 8k trailer. I did try without the trailer too, but perhaps didn't find the right conditions for 4th.
Got her to lockup readily several times, but it really needs a steeper grade, probably 6%+. I live in a hilly area and that was the ticket to getting it to lockup in 4th while in "D".
Previously I was on a long road trip focused mostly on lockup with a 8k trailer. I did try without the trailer too, but perhaps didn't find the right conditions for 4th.
Got her to lockup readily several times, but it really needs a steeper grade, probably 6%+. I live in a hilly area and that was the ticket to getting it to lockup in 4th while in "D".
No it doesn’t. Prefer the 6 speed in my LX to 8 in my Cruiser too.
It’s kind of dumb if you ask me to kill the NA throttle response experience by hunting down 3 gears when you actually need the motor.
For what even, dont the 2015 and 2016 get the same MPG? Perhaps some benefit in towing or acceleration. Someone post the numbers I’m too lazy right now.
But still, IMO not worth it. I know @bloc has told me before he thinks it would be nice for gear advantage on 34”s+. But bloc, didn’t you just post about the final drive ratio also being lower? I need to educate myself on the mechanics of all this. What are the technical pros ?
