My new 347

Dono · February 1, 2018

Well, Chris of Lentech emailed me back. The trans has to come out. Here's his answer:
"The solenoid pack on the valve body cannot cause a flare as they are ON-OFF solenoids. They will work or not work (ie: you will have all gears or not). The potential causes of a 3-4 flare as I see it are larger than spec clearance in FWD clutch or worn OD band. Just to be sure you don't have a pressure problem, you could put a gauge on main line and verify it is in range."

I'm certain my pressure is ok, but even if it wasn't, either the trans or the motor comes out (If the pump needs doing, the whole trans gets massaged). Don, it looks like a higher performance Forward clutch drum will be going in.

Dono · February 1, 2018

Tim, I think your right about the od thing. I have corrected the shifting in and out of od at low speeds, but it looks like the damage is doen.
No rush, but if you happen to be talking to your trans guy could you ask him if he'd be willing to do my trans?
If he will, ask him about the Sonnax Forward drum. Sonnax Smart-Tech® High Capacity Forward Clutch Drum Kit - 76655-01K

If he thinks its not a bad idea, ask him if he would source it, or if he'd prefer I did. If he is going to start collecting parts ahead of time, I can give him some cash so he is not out of pocket.

CDW6212R · February 1, 2018

Are you guys in OD with high throttle much at all? Shifting at WOT is really bad for the OD band, but easing into the gas while at speed shouldn't be as hard on it. But it is a weak link, and there isn't much to do about the OD piston size etc. I'm hoping a 3.73 gear and 29" tires will be fast enough in 3rd. I don't want to change both diff's.

CDW6212R · February 1, 2018

Try this link with Summit, this is the version with an 8 clutch capacity, the other is seven, both made the same otherwise;
https://www.summitracing.com/parts/sox-76655-01k
It's gone up, $189 now, I got one for $185 and the other version on eBay for $150.

Was your trans built, or original? Factory clutch clearances are typically loose, which softens shifts and also makes the trans need clutches sooner. Most performance builders will set the spec's down near .010 per friction/steel, stock is easily over .015 each.

Dono · February 1, 2018

If I'm in od, I never bang on the throttle.
I am just off the phone with Tim's transmission guy.

Extremely knowledgeable. I started by telling him how the truck had been modded and how I had troubleshooted by moving the 3-4 shift up to at least 55mph via tuning the pcm. Eric understood exactly what I was talking about and had an immediate suggestion for me. That impressed the heck out of me.

First, he said that what I'm describing is very unusual, and I'm probably experiencing a 3-4 tc lockup immediately after shift. He asked that I put the 3-4 shift back where it was, and move the tc 3-4 lockup out of the mix so that after the 3-4 shift occurs the tc won't lock up. He is pretty sure that we will find that the issue is gone.

It's more than possible that this is the issue as I have been moving shift points around, and had moved them to factory except for peak rpm. Factory shifting is probably just not going to work for my truck anymore. More to come tomorrow. I wish I had my tuning dongle and current tune with me at work to make the change and test on the way home.

CDW6212R · February 1, 2018

I wondered if your symptom might be the TC locking, but the flare description made me hold that idea back. I hope that's it. You'd be happier to build a 2nd trans anyway I'll bet, then you could swap it when you are ready to.

vroomzoomboom · February 1, 2018

Dono said:
I wish I had my tuning dongle and current tune with me at work to make the change and test on the way home.

now i bet your really itching to get home lol
yea, eric is a freaking encyclopedia when it comes to transmissions. and most things automotive as well. there is a reason why he can do this stuff on his own, at is own place. there hasnt been much, if anything at all that me, and any of my friends, or anyone that i have told to go to him for something that has stumped him. as well as, you know he is a strait up guy when he tells you to try this or that over the phone FOR FREE instead of "yea, just drop it off, and leave your money behind". he is also one of those guys that doesnt want your business unless you need him if you understand what i am saying. thats why every trans i have ever needed done (with the exception of the one thats in evil, but he did have a part in it) has gone to him, and i have never had a issue ever

Dono · February 2, 2018

This has been a night of pure frustration.
I first put all shift points of each gear and each tc lockup on a spreadsheet and made sure that the tc was not being commanded to lockup in any gear before the shift of that gear. went for a drive. flareing still.

ok, loaded another tune that set lockup on the tc in 3rd and 4th to 80mph and above. I couldn't really perceive a flare. That's good I say to myself.
Next, I load the next tune that allows 3rd lockup, but keeps 4th lockup at 80mph.....and a flair happens. Makes my head hurt. :banghead:

I have now created a tune that will not allow 3rd or 4th lockup below 55mph, but at light throttle 3rd and 4th can be commanded at light throttle. Hopefully that will give me some clue. I guess I better make another that allows 3rd lockup again and see if I get the flare.

I also imported a shift lock schedule from a tune in October that I definitely know did not have a flare when shifting. I'll try that one, just to make sure I am not going crazy. :banghead:

I think there is a problem, I just need to diagnose it.
I should create a datalog of the shift pids and tc pids with rpm and throttle position. It's so f'n cold out I just don't want to sit in the truck and play with a laptop. I'm starting to think this is the only way to really know for sure. I'm sure I can muster the energy (not sure about the desire, but I'll have to find it) this weekend.

Their was a faint glimmer of hope this afternoon, but thats fading again. If the trans is coming out, the right thing to do is to be able to say exactly what the issue is. I think we all know what its like to have someone drop something off with absolutely no clue whats actually wrong.

vroomzoomboom · February 2, 2018

want a copy of my shift tune? and if you need or want, i can make a trip to your place and either ride shot gun, or drive while your doing the computer stuff

Dono · February 2, 2018

I'm going to bed to curl up in the fetal position. Tomorrows a new day. lol

CDW6212R · February 2, 2018

Wake up, it's 25 outside now, plenty warm to do car work. My hands are a little numb, I just got home from work.

Does the ATF look good, almost clear and no odd smell? If it is, then the band shouldn't be fried. Keep at it.

Dono · February 6, 2018

I have been working on the shift/lock schedules on both the tc and gear shifting.
The issue seemed to be tc 3rd lockup. I moved the lockup on 3rd up to a minimum of 80mph and the issue went away interestingly enough, truck felt pretty good with no lockup in 3rd. I'll keep playing with it. Tim's trans guy for the win! Thanks Eric!!

On another note.....I get in the truck and pull out on the driveway and wait for my wife. She says " Whats all that oil on the ground in the garage?" I said "What?"

Puddle of oil just to the inside of the drivers side tire, not diff oil, not brake fluid. Engine oil. Hmmm I say to myself, that's kinda where my turbo oil feed line and connectors with the one way valve. No biggie I say.

I get home, and the leak is much worse. Garage is cold, I'm tired, and now Im miserable. I check the 4AN connections and they are tight. WTF? So, I clean the area up and start the truck with the tire off so I can see and am not rolling around on the frozen ground with a piece of cardboard that keeps sliding around. I can clearly see the braided line is dripping about 3 inches from a connection. What? No chafing, no nothing. I was able to cut the line and had enough slack to put another end on the line. All things considered, the story ended well. A burst would have meant little or no oil to the turbo or the motor. Maybe braided line isn't the best stuff to be using for fuel and oil making long runs to the back of the truck.
Just another shared experience for those that are modding their daily driver. Listen to that voice in the back of your mind telling you not to do it.

CDW6212R · February 7, 2018

Tell that voice to shut up, fun is what makes life interesting.

vroomzoomboom · February 7, 2018

eric's done lots of tranny's for me. if i have ever blown a tranny, he fixes me up

how long of a line is it? i have some 6 and 8 laying around, but i think the 8 might be 6 foot, and the 6 might be 4 foot long

Dono · February 7, 2018

It's all good Tim. its 4an that goes from my oil sending unit to the turbo.
After that, I think I better have a full length of 4an (Higher quality, not the Chinese stuff I used) with ends and a joiner just in case I have the issue again and don't have time to run a new full length.

Dono · May 15, 2018

Ok, as some of you know.....The crank thrust is trashed again on my motor. After seeing all the oil under my truck, I knew, but didn't want to know.

Popped the belt off, grabbed the crank pulley from underneath, and pulled the pulley front to back....Clunk, Clunk. Followed by that special sinking feeling.

Motors out and at a machine shop. This guy is a bit of a mad scientist. He has different cnc's for everything that can be cnc'd, including blocks.
Dimas Lourenco

Now, I'm not sure that the issue is something in the motor wiping out the thrust bearing or something pushing on the crank from the trans side.

Off I went to try to understand.
Here's what the trans guys over at Yellow Bullet think:
Trans line pressure is too high, and the high line pressure is pushing the converter in to the flex plate.
What does that mean, how do I test for it, and what do I do about it if its too high?

Finally someone over there spoon fed me the information I needed since I don't even know what I don't know on this.
What is being said is: The line pressure going out of the transmission to the coolers might be too high. This means that there likely is too much restriction going thru the coolers. One of the guys said he does not like to see more than 80 psi at 3000rpm at the line going in to the cooler.

What am I going to do?
I'm going to add a oil pressure sender (The same oil pressure gauge I'm using for oil pressure and just switch back and fourth as required) to the line out on the transmission (It's the metal line that's physically lowest on the trans). Then when I get the motor installed, I can check engine oil pressure, then move the sender wire to the transmission oil sending unit. The oil pressure gauge I have is only 100psi, but that's enough to tell me if I have a problem or not.

If trans pressure is an issue, and its a good thing since I probably found the smoking gun
I will try lowering shift pressures in the tune temporarily and see if that helps.

The pressure fix options are:
1. Add another trans cooler in parallel to the existing coolers (It would need to be a design of the 'stacked-plate' variety to ensure high flow).
2. Hutches transmission (Over on YellowBullet) sells a bypass kit that will bypass the coolers for anything over 80psi)

The parallel trans cooler will probably be the least expensive option, but I need to pull the front bumper off and see what I have for space, and I also wonder what happens partially bypassing the trans radiator atf cooler/heater for winter driving. I'd think heating the oil in the winter would be a good thing for trans longevity.

In the mean time, Dimas is going to go thru the motor and see if he can find an oiling issue, or some other reason for the thrust bearing getting destroyed.
He also wants to engine dyno the motor before giving it back to me so he can be sure his work is good.

The guys at YellowBullet have also installed torrington bearings on the crank thrust to take the load off of the existing thrust if there is an issue. They really don't think I should need this since I'm not exactly in the horsepower arena that most of those guys play in. I will discuss this with Dimas though.

vroomzoomboom · May 15, 2018

how is it that i have gotten away with it thought? i mean, the last time i remember we had my line pressure jacked.

Dono · May 15, 2018

I have no answers...Only things to check.
I'm certain the TC is not binding on the trans output shaft.
I really don't know, but I really want this bearing failure issue to go away.

gmanpaint · May 15, 2018

Dang, I feel for you with this. I hope it is diagnosed, and fixed. All these what if's and maybe's are scary, as they all cost big bucks and time to do.

CDW6212R · May 15, 2018

Ditto, I want you to not have to worry about the thrust bearings again.

Have you discussed that with Alan of DD before? I haven't spoken with him for 2-3 years, but he's one of the best 4R70W builders I know of.

Check the pressure from the line port also on the side of the trans, that's the baseline for the rest. Who built the trans, and how sure are you that the end play was set correctly? Any replaced parts can alter the end play, and that requires a different plastic end play shim(the plastic thing just behind the pump, they come in thicknesses that range about .050 low to high).

I'm glad the engine shop wants to dyno it, that sounds like they really care about it.

My new 347

04 GT

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04 GT

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Elite Canuck STOCK SUCKS!

04 GT

Elite Canuck STOCK SUCKS!

04 GT

Hauls the mail.

04 GT

Hauls the mail.

Elite Canuck STOCK SUCKS!

04 GT

04 GT

Elite Canuck STOCK SUCKS!

04 GT

It's Always Something!

Hauls the mail.

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