Transmission Upgrade Project
 

I'm starting this thread so I can share my ongoing transmission experience with the everyone. I'm hoping that my course-of-action will lead to a better option than rebuilding or replacing a 4T65-HD Tranny.

The first part of my odyssey is here: https://ls1tech.com/forums/ls4-front...yesterday.html

For those of you that haven't followed this, here's a quick story what me and my '06 Impala have been through:

In April of this year, the local Chevy dealer rebuilt my tranny under the GM Certified 5/100 warranty. This was done because the torque converter clutch came apart, and the material that contaminated the fluid wiped out the 3rd gear clutches. The car had 58,000 miles on it. A couple of weeks ago (22,000 miles later), my wife noticed that, when slowing down to a near stop, then accelerating again, the car would sometimes freewheel (as if it was in neutral) and not accelerate, only to slam into gear and go a second later. We took it to the dealer, and the intermittent problem showed up for them, too. So, they're putting a GM remanufactured tranny in it under warranty.

That's where we are now. The tranny is being installed today and I should have the car back later on in the week.

My concern now is, how long until this one has a problem?

Well, I've had several converations with Dave @ TEP, and based on his recommendations, after I get the car back and establish that the remanufactured tranny is working right, it will go in for some upgrades. Dave indicated that, since the trans will be basically be new, then it won't need a complete overhaul to be upgraded. So, he has recommended the following upgrades that should prevent the most common problems we see in these trannys:

Upgraded/Rebuilt Valve body & spacer plate: This includes some machine work, as well as all new solenoids and valves. The modifications should prevent some of the other common problems like harsh shifts.

Sonnax Converter Relief Valve: This valve bleeds off over-pressure when the torque converter clutch is engaging (lock-up). The factory valve bleeds off pressure at too high of a threshhold, which, over time, destroys the TCC. This is what caused my trans to fail the first time, as well as many other people on this board. The Sonnax valve has lower threshhold that doesn't overstress the torque converter clutch.

Seal Kit: This kit contains the long style lip seals that prevents issues like converter oscillation, and slow gear engagement when cold. We also think that a leaky seal is causing the issue my tranny is seeing now. This type of seal design is supposed to last a lot longer than the stock shorty seals.

The interesting thing that I've learned in talking to Dave is, GM made a bunch of compromises in our trannys so that they shift smoothly. When you couple that with the fact that LS4 engine is at the outer limit of what a 4T65 can handle without mods, it's no wonder the problems are so widespread.

These parts, along with the needed replacement spacer plate, are coming from TEP. I have TransGo shift kit sitting in a box that and will be installed when the other parts get here from Dave. The total cost of the stuff from TEP is about $405. My buddy's tranny shop will handle the work and is charging $400 to R&R the trans, and another $200 install the valve-body, shift-kit, and tighten up the 2nd and 3rd gear clutch clearances.

So, for around $1000, I SHOULD have a transmission that won't be giving me anymore trouble, but who knows. This is the most cost-effective setup me, as I only have a mild bolt-on car that isn't really beaten on but sees a ton of highway miles. I could have sprung for a TEP Street/Strip Trans, but the cost of the tranny with shipping and installation would have been around $2250, which is out of my budget. What I hope this will give me is piece of mind knowing that my trans is no longer a ticking time bomb.

I know this solution won't be for everyone, but for some who are having problems but not seeing material in the pan or if you're not having any problems yet and don't want to worry about them in the future, this could be a lower cost alternative. Also, if you're making big power or your animal behind the wheel (Travis), this may not be for you.

Anyway, I plan on using this thread to document each step in this project and will report the results, good or bad.

I just want a trans that WORKS!

IF you have the money can plan on continuing to add to your car, performance wise, go all out. You know.... just in case.

Its just his DD,he has the GNX for the performance...

That's interesting to know. Compared with our '95 Z28 (automatic), the GXP shifts extremely smoothly. I really prefer a harsh shift that kicks under hard acceleration like the Z28 does.

Are there currently aftermarket upgraded transmission for our cars that handle the power better? If so, what are our options?

Transmissions are too complicated for me to pretend to know anything about the bits and pieces. Seems like it'd be easier to purchase a brand new upgraded one when the old one goes bad.

Sorry if i missed it saying it was for DD purposes only. The reason i said that is because after only a two and a half months i was already grinding the input shaft.

Hope I didn't come off like a "Dick",just thought you saw his sig...My bad ,I member you tellin me your not on all the time...you might have miss Mike's other threads,about his tranny problems...

Vectus you got your tranny threw TEP?

No no not at all. i did, and saw that he had it tuned, didnt know if he was going to go further than that. Yea i sure did miss it, and i decided to throw in my .02 either way because of what was happening to my input shaft in such a sort time.

Yes sir, i did.

I too prefer a shift you can feel, and these mods will definitely help with firmness.

You can buy an upgraded trans from TEP, but it will cost $1650 to start, plus shipping. Obviously, if your tranny dies and you need one installed anyway, it makes sense to go the TEP route because a GM Goodwrench reman costs about the same.

And whether you do a full tranny swap or what I'm doing, you'll need a mechanic if you're unsure of how to do it, so it really just comes down to whether your trans is in good shape or not.

I wish I had a GNX! I just have to settle for the GN!

Thanks for trying to keep my thread straight, Dom!

Well, just got a call from the dealer and the car is ready. I'll be picking it up this afternoon and hoping that everthing was done right.

On a separate note, my "spare" trans is now on it's way back to TEP in Indiana as payment for the mods I'm buying. Hopefully, I'll have my new valve body and soft parts in the next couple of weeks.

Right on Mike glad to hear everything worked out in your favor.Yeah my bad,thought you had the GNX but you still have a gem in your hands.

07 transmission
 

I have a couple of questions on the 07 SS transmission...

first, does anyone make a higher capacity oil pan?

second, When is converter lock up supposed to occur?

Jim

Well, I got the car back yesterday. New trans shifts okay, but the new converter seems looser than the last one. The result is even sloppier feel in town and higher trans temperatures, especially when the converter is unlocked.

I'll be driving it around this way until my valve body shows up, which hopefully isn't anymore than a couple of weeks.

I think there is one out there, but supposedly, it doesn't fit real well and leaks.

I think lock-up occurs in 3rd and 4th around 45 MPH at cruising speeds.

LS1,

Do you have another trans. coming from TEP? I love mine! From 1st to 2nd if I am on it she'll break the tires completely loose. I only have done that once and haven't done that again... lol... Do you have a shift kit too? I have a TEP Precision TC (stock stall) that is like 150.00 or 175.00 (can't remember) and it works great! On a 50 degree day my trans. doesn't see over 152 as a temp. What's the trans. temps. at now?

-Mike

If I remember right, 210 is normal operating temp for our cars according to the owner's manual. I believe it also says if it's above 220, that's not normal. Mine is usually between 195 and 210 according to the DIC. On a hot trip during the summer, it was at 220.

Glad to see you back on a trans thread where you belong!

I don't know if you remember, but I had my trans rebuilt by the dealer earlier this year, and my trans temps went up about 10 degrees across the board. Well, it died again so the dealer put in a remanufactured one and a new converter. Now, the trans temp goes up even more, especially when standing still. I saw it climb from the 160's to 186 last night just sitting in a drive-thru. Even on the rebuilt original, it only got that hot on long grades in the summer. Oddly enough, when cruising at higher speeds with the converter locked up, the trans actually runs cooler. I saw 135 this morning on a level road in 55 degree temps after seeing 160 on a hill.

Since I already have a basically "new" tranny, I'm getting a TEP valve body and adding a shift kit. My buddy's shop is also doing some modding of the clutch clearances. I talked to Dave at TEP several times about this, and for my application and use, he thinks it's the right way to go.


I think the highest I've ever seen is about 208, which was last summer, going up a 7 degree grade. Normal for me with the cooler (and before the remanufactured tranny)was about 165-170. Normal when it was totally original was about 145-150 with the cooler.

Totally normal. Less heat is generated while locked as opposed to all the friction producing heat while the converter is slipping. The higher the stall the hotter the fluid will get.

Actually, I didn't explain myself correctly. The old tranny ran cooler with the converter locked, too. The thing is, it would run in the 140's-150's in the same situation that this new one ran in the mid 130's.

LS1,

Do you still have the trans.fluid running through the radiator? If so, try just running it through just the cooler and also you can put in a 160* thermostat and get a tune to turn the fans on earlier. This will do absolute wonders for the transmission. Come to find out on my last build the person putting in the input clutches put them in backwards. This was why my trans. ran at 244* right after it was put in the car and it only took 2 miles to get that hot. Good luck with the build.

-Mike

Hi Mike,

The radiator is still looped into the trans fluid circuit. When the rest of the work is done, the radiator's trans cooler will no longer be used. I've gotten lots of advice to bypass it, and that's what I'm going to do.

I've never thought of going to a cooler t-stat on this car. Where is it and how difficult is it to change?

Interesting to know what was causing those high temps in your old trans. I always guessed it was the converter. Sucks that it was someone else's carelessness that resulted in you having to do it again.

I went with this thermo. It didn't ever give me a check engine light even when I had the stock tune. Your milage may drop a couple of tenths but it keeps everything nice and cool. It isn't that hard to change. If you do decide to do it just PM me.

http://www.slponline.com/view_product.asp?P=100228

I thought I had a bad converter too until I sold my old build and the guy who tore it down told me what he found. Nice, huh? I couldn't be happier with the TEP trans. It is a nice firm shift and is worlds apart from a stock transmission.

-Mike

Cool...Same t-stat as an LS1, so I might even have one handy.

Thanks for the suggestion, Mike

No problem. The car also still gives off good heat with it too, even in the winter.

-Mike

Update:

Drivability with this remanufactured trans SUCKS. I think it's all related to the torque converter that was installed with it, as it seems to act like it's got a lot of stall. I spent about 20 minutes on the phone with Dave at TEP, and it looks like I'll probably be buying a new converter to go with this valve body. I'm even considering just getting a TEP trans, if I can make a good enough deal.

This is getting VERY old.

A sugestion...I am more famliar with SCT than Diabo Tuned. It should be possible to program converter lock up just after shift to second or before shift to third. Less heat and better driveability. I think delaying lock up is like driving around slipping the clutch. Let me know what you think.

Jim

That makes perfect sense, however, we have no TCM control with the DiabloSport, so I don't think there's much Lew can do in terms of lock-up.

I think that would be a band-aide anyway, as the converter is obviously WAY out of spec.

Another update:

When getting ready to go out the another night, I walked out to the car as my wife was putting it in gear to back up. As soon as she put it in reverse, the trans began to whine. I had her run through the gears, and it only makes this sound when in a forward gear or reverse. I talked to Dave at TEP, and he thinks it's either the converter or the pump. Either way, it's going back in to the dealer AGAIN.

As much as I liek the car, I'm really starting to regret buying it.

I am going to go out on a limb and say it's the converter. I bet they even put your old one back in when they put the new trans. back in. Just a guess...

-Mike

The dealer documentation says they put a converter in it along with the tranny. I'd tend to believe that, since the car is behaving completely differently...It's acting like it has a stall converter and is generating much more heat than before under the same conditions. Also, the trans didn't make any noise before.

I guess we'll know more when I take it back to them next Monday!

Man I hate to see you with all these transmission problems.

At least it's all being documented.

Thanks, Man. I've been pretty patient with this car, but I'm getting close to the end of my rope.

Update: 1/10/2011
 

1/10/2011 Update:
Spoke to the shop that's doing the work this morning, and it looks like the car will be done on Wednesday. Here's a few things that I found out when I talked to Brian at Reb's:

The GM SERTA transmission the dealer put in my car about 3000 miles prior to this work is in good condition. There was no material in the pan or valve body, everything was in order. The only thing remotely out of the ordinary was that some of the steels had some burn marks, but this was most likely because they were reused from GM's SERTA parts bin. Brian replaced these with new ones, just to be on the safe side. Needless to say, I'm shocked at how good the condition is of this remanufactured tranny. I'm much more confident that I'm building on a strong foundation for a reliable transmission.

One of the other things Dave @ TEP recommends is to take some of the clearance out of the 2-3 clutch pack. When Brian measured the clearance in my 2-3 clutch pack, it was .150, which is in-spec, but very close to the limit. This was tightened up quite a bit before reassembly. Hopefully, this will have a positive impact on 2-3 shift quality and speed.

The TransGo shift-kit is going in today, and that should wrap up the transmission surgery.

So far, so good. I'll post when I know more!

BTW: The new torque converter than came with the SERTA transmission is in good shape, if anyone is interested. I'm ordered a new converter to go with this valve body just in case this one was trashed. Since there was no material found in the transmission, we can assume that the torque converter clutch is still one piece. It's only got about 3000 miles on it, and seems to have a lot more stall than the previous converters I've had. Drop me a PM if you're interested.

But do you need to take the trans out to install a new valve body

You either need to drop the subframe or pull the trans completely to replace the valve body. There's no room to get it out with it in the car.

wow that blow a big one i thought you would be able to get to it threw the pan like most other cars

Nope, it's not in the pan. It's sits up vertically.

How much was the relief valve? I am digging into mine this weekend again to add a magnet, shift kit, and replace the pressure solinoid. figure the relief valve couldnt hurt.

I believe he said in there you need to pull the trans to replace the valve.

It is cheap...

I hope this link copies right: http://www.sonnax.com/product-lines/.../filter?filter[make]=1&filter[unit]=231

nope..... im not sure if i feel like pulling the trans.. but i guess if i am in there i may as well.

The valve is about $5.00. And after spending some time at the shop yesterday when I pickled up my car, I learned that it MAY be possible to replace this with the trans in the car, but it's exceedingly difficult. I was told it's probably easier just to pull the the tranny.

For results of this project, see https://ls1tech.com/forums/ls4-front...-upgrades.html

have a link to order it?

I got mine from Dave @ TEP. You can probably just call him and he could probably have it to you by the weekend. He's in Indiana.

Mine totally blew up last night so i need more than the valve now. haha

i got my new trans from dealer last month,put the cooler and transgo shift package from tsp-like night and day don't care if they don't cover it as they tried to find something i did to trans last time-nothing-but they looked then replaced it took 3 weeks no courtesy car nothing,was pissed now not since upgrades which i wouldn't have known about except for this site,thank you

3 weeks ? When i had my 2002 monte carlo i had several issues with the transmission. I had it in the dealership literally 5 times. First the sungear shatterd when i put it in reverse. Then it had a issue with the valve boddy where it got nicked and would cause the computer to go into some type of limp mode making it 100% pressure. Then where they took it apart it leaked where they coudnt get it to seal anymore and needed a bell. Then after they replaced the bell the car would drop out of gear at idle "seal issue" then after they finally got everything fixed i got T-boned , anyways during all of that i got a rental every time and they fixed it no questions asked , it was one of those certified 100,000 mile warrantys. squeaky wheel gets the oil , or use a hammer and start making people sqeeke

trans
 

yea service writer told me they want dealer to try to fix before replace,they put solenoids converter,other shit before they even called me,they said i could drive it until they get parts,i said no,they took it apart 3 times when i told them it was gone.clowns,i took it off lot and thought i felt shudder but i put some miles on it and it seemed fine,but now really fine-love it with the transgo beef up and the diablew tune-rocket lol