if something in the trans broke you would more than know it for sure now , This I can be sure of . I will also say nothing in a trans can make a bang noise, Trans can do 3 things shift , pull or slip . Now it can shift so hard it makes the drive train bang , However I would find that unlikley at a very specific RPM and speed or area as the hydraulics nor mechanical parts change with rpm or throttle or speed. All that does change are presures which are set by the PCM.
But I guess if the cooler was not flushed something could have gotten in the PR valve made it stick at vey high line then when cleared it went back ?But that would have been a 1 time event and done.
I honestly have no idea what to tell you except what I already have, Im not trying to argue just honest.
We have at our disposal no method to test, no method to datalog or anything . So for now all I know to advise is since you said its doing ok now and the 2-3 low throtte is tolerable now , As I said drive it , give it hell if you like. It will live or not , Its that simple . I dont know what else to say or do except that is what I would do drive it .
Then if it breaks we can solve it then one way or another.

 

I am in complete agreement with Frank. I don't think this is an issue of an incorrect converter spacing. Transmission just don't work that way. If the converter spacing is so wrong that the car won't pull at idle, it sure isn't going to pull under throttle. So, lets move on from this. Sure, the cooler may not have been flushed, but then again, I agree with Frank that is not all that much material in the pan, clean it out and run it.

What Frank does with his valve bodies makes the 2-3 shift happen so fast and firm that at the RPM and MPH the complaint is happening there is not much of a load on the driveshaft or ring and pinion. When the shift happens, it shocks these parts and slams them into each other taking the slack out of them. That is the bang that you are hearing. I know this because my car is doing the exact same thing at that exact same RPM and MPH. I have learned how to drive around it because I have been too lazy and busy to try and tune it out.

For what it is worth coming from a guy who has been and auto tech since 1982 and rebuilding transmissions since 1984. I just finished building a 6L80 last week. I feel you are making something out of nothing about the install, but the bang is for real and a stockish valve body or tune will take care of it. My 2 cents.

 

Yes BBOND105 my VB shift kit and the sealing up and modified 2-3 valve primary funtion is to make the 2-3 shift happen as quicky as possible as the 3-4 clutch regardless of build is and always will be short of a 4L75 drum the weakest clutch set and most common failure point in the 4L60E . Clutch area is terribly small in the 3-4 set and attempts to increase it only result in poorer and poorer heat disipation. The ultra quick shift massively decreaase this heat up happening during the shift . But like all mods has a down side in feel and to what extent varies car to car truck to truck , rear ratio to rear ratio, I went back last night and returned my trans PCM to the stick tune (I had anticiapted I would not like the early shift with the 2800 stall and had preemptivly raised the low part throttle shift points 20 percent) So I never experience the low part throttle (bang more like a clunk) . But was able to duplicate and it does indeed exist . To me its livable but like I said would be different car to car.
I have given consideration to it and ways to mitigate it, And no way exist as far as the shift kit without undoing the point of it.
I know it works and accomplishes the goal well as two years ago and yes with the customers agreement I built a unit with the thinnest frictions and steels .062 and machined plate to allow 10 3-4 frictions. He has 800 rwhp and has run many many track passes with a 5500 lb truck. I tore down to do what is actually one of my frist refresh , Its a local so he dropped it off . He said it was working fine but wanted to make sure it was ready for next season (Note he also tows a small camper and boat with it in the area with lots of hills here ) What did I find? A perfect 3-4 set with no indications of heat or warpage. In fact the only issue I found was some unusual wear on the pump bushing to one side.
But this to me proves the shift kit does exactly as intended as a 3-4 set with minimal heat disipation held up .
I because of this ^ thread was considering altering the shift kit to mediate this (bang /clunk) at low part throttle , But then ask myself wait what am I building for , Comfort or performance / durability ? and the LATTER is the answer.
While up till now no one had brought the (bang/clunk) to my attention I am now aware it exist as part of the build and nature of and will start noting that to all future customers but will not change the build or nature of the shift kit as I feel it would be self defeating of the goal.
As for the OP situation I can offer to send a unmolested 2-3 valve to replace with one in existing VB that can be changed without removing the VB which should mediate or eliminate the issue . Simply remove the 2-3 solenoid and 2-3 VALVE TRAIN AND ADDED SPRING and install a stock one in its place.
While I still stand the best way to deal with it would be in the tune to elimiate the conditions where it happens which according to my own experements with my own car last night is as simple as raising the low apart throttle shift points (to me honestly 1500 rpm shift to 3rd gear seems ridiculosly low and with a 3000 plus stall would feel yuky for no better word, I know on my own car it feels like slipping even with a 2800 stall ) Changing the valve however should mediate it adequatley though perhaps not totally as the FT OVERUN mod I am sure plays into it also as without it the sprag would be in a more or less freewheeling mode in these conditions.
Also as I am sure you have been in the tune GM actually puts negative numbers in the presure modifiers under this very set of conditions , I assume to mediate it even stock.
Anway today I will certainly be raising my part throtte shift points back up as I hate the stock tunes overall feel and not just the (bang/clunck) which IMO is tolerable but slippy feel of the whole set up being so very far below stall speed .
On the initial not pulling my best guess is cooler was not flushed possibly withs some particle stick or blocking feed to the 1-2 valve with possible 2nd gear starts resulting with a quick jump down to 1st on throttle or some issue with the stock converter made to stall above 3000 (BAD IDEA ON A CONVERTER as it would really be a very inefficent heat machine) But since gone not something to be concerned with.
The material in pan normal to above average good for a first filter change particualry not knowing if or how well cooler was flushed or what inside of the restalled stock converter was like (would love to see the little filter in the pump and ws even thinking if off the bat that filter was blocked could have restricted converter flow and also cause the no pull at idle issue due to poor converter fill / flow and te sudden fix well as we have all seen he screen blew out and opened it the flow up which would explain the sudden fix ) But again if all is working is working as of now I would certainly not pull my own trans in that situation I would drive and go.
Also to the OP who I am sure is reading this also (reason for no separate post) I am extending the 1 year warranty to 2 years to hopefully give him more peace of mind.
Now out to work .

 

I like the way Franks kit does the 2-3, it as Frank says addresses the main failure point in this model transmission. This is a performance transmission not a shock rebuild. I suppose OP got a little more performance than he expected. Anyway, Frank has given the OP several options to make the transmission shift more to his liking, which is more than most would do. All OP has to do is pick one and move forward.

 

Did yours make a loud bang that shook your car after it was installed?

When yours shifts from 2nd to 3rd at 1,500-1,600 RPM (light throttle under 20 mph) does it make a clunking metal on metal noise that can you feel
in the seat?

Was there very much metal in your pan after 500 miles?

 

Why not make and post a video of this bang?

 

Yes, when shifting from 2nd to 3rd gear the car, not the transmission, makes a clunking sound that can be felt in the seat.

I built my own transmission using Franks valve body parts. Every rebuilt/new transmission that I have ever removed the pan from has had material in the pan. This is normal, some of this comes from the bushings and clutches wearing in and trash that does not get flushed from the cooler and lines. This is why Frank recommended changing the fluid at 500 miles.

Frank has added another year to your warranty, offered to redo the transmission to your liking if you would send it back to him, offered to send you another valve body and offered to send you an unmodified shift valve. He even offered to adjust the transmission tune for you; all you have to do is email him the file. I don't know what more Frank or anyone else for that matter can do to make you happy.

What do you want Frank to do? Have you even called Frank to talk to him?

It has been explained to you that this is a performance transmission that is built for performance durability not for soft smooth shifts. This is no different than ordering a full-on race cam shaft and installing it in a stock car expecting it to idle and drive like a stock cam shaft. You received the transmission you ask for. It seems to me Frank has gone way beyond what any company would be expected to do. Try warranting a performance engine that doesn't perform the way you expected it to.

I hope future readers can see what is going on here and not use this thread to turn you away from using Frank for your transmission needs. Frank could have built the OP a stock transmission, had that been what was ask for and he would have been very happy with if that. Frank was asked for a performance transmission and that was what he sold him.

Frank has a spotless reputation here and is always trying to help people on the forum with their transmission problems. I will purchase more of his valve body kits when I have a need for one and if I didn't build my own transmission, I would only purchase a transmission from Frank.

 

I have franks transmission in a truck thats close to 800 wheel and handles it flawlessly so I wouldn't think twice about purchasing another transmission from him. Frank even gave me advice on a buddies car's transmission and Frank didnt even build that transmission so he had no obligations in any way shape or form to help out with that one and still chose to give advice.

 

No one is attacking Frank’s build. I’m just trying to figure out if the slow speed clunk is normal or not. I didn’t have the best expirence during the install so didn’t know if it was an install error or if everyone else was clunking around town.

Where is your clunking coming from? Did it clunk with your old transmission?

 

Post a video!
and obviously our old transmissions wouldn't have done it because we went from stock to performance. Performance obviously isnt going to drive like stock.

 

I’ll see what I can get. I understood that it wasn’t going to drive like stock. But I expected it to shift harder at WOT than it does when it shifts at 1,500. But that’s not the case. WOT shifts are good.

How long before clutch material stops showing up on the paper towel after you wipe the dipstick? It’s been drained and filled numerous times now in 500 miles and the napkin always comes back dirty.

 

I cant speak on that as im not a transmission builder but i can say my transmission does shift the same way. Make a video, post it on YouTube then post the YouTube link here.

 

No, my old transmission did not shift as quickly and firm as this one. The noise seems to come from under the rear seat area. Are your torque arm bushings, u-joints in good shape. How much back lash is in the differential and axles?

 

It's not that it is shifting harder at this one area, it's shifting at a time when the drivetrain is not loaded. It like revving the engine up in neutral and then pulling it into drive.

 

I don't think the OP was ever blaming Frank or his trans build, I think this reply is a bit defensive and sort of misses the main points of most serious concern.

- The initial "bang" that was so loud and harsh that the OP thought his driveshaft fell off, so loud that he pulled over to check out the car. This is not normal, and it may have nothing to do with the actual new transmission itself, and apparently it didn't happen again so it's not part of normal operation. Again, I suspect something less than savory might have happened with some part of the installation process (not necessarily limited to the converter spacing, there are other things that could have been corrupted during this process by an incompetent shop).

- The shop in question returned the car to the OP with a trans leak, something unrelated to Frank's work. This wasn't Frank's fault either, it was sloppy work on the part of the shop. Again, making said shop (and their quality of work) suspect.

- The car didn't initially pull forward on level ground at idle. I remember this being mentioned in the very first thread that the OP posted with his concerns. I was the only one to tell him that this was not normal for the application, some other folks insisted it was fine. Low and behold, something changed and now it pulls forward just fine on level ground at idle speed - just like it always should have. Frank could certainly be correct that some debris (from a poor flush by the installation shop - again, questionable work on their part) had caused a temporary clog that has since cleared itself. Or, there could be an issue of some sort with the converter itself (again, certainly not Frank's fault), but only time will tell if this issue returns.

Ultimately, I think the OP has had some valid concerns here, mostly with things that are likely the fault of the installation shop (especially the post-install leak, poorly flushed lines and cooler, etc.), and that initial noise would probably have been enough to cause anyone to be concerned. My guess is that the OP would likely not have been nearly as concerned by the [normal] extra-harshness of the low speed shift if that was ALL that had been noticeable from the beginning. I think the other issues, all of which are certainly not normal (leaks, insanely loud initial "bang", no forward movement at idle), have set him on a path of concern. But, I don't think he (or anyone else) is pointing a finger at Frank or his trans. Frank has obviously been nothing but helpful here, but no amount of tuning or reworking of the trans will help if that shop damaged something else with the driveline or suspension during the install that might have led to the initial insanely loud noise.

My suggestion? Have a more competent shop, specifically one that specializes in gears/axles/driveline, look the car over and test drive. Explain to them that the trans is a performance unit and it's supposed to shift hard, but that something else happened on the first drive that may have been indicative of an issue with the rear or driveshaft or related suspension. If everything checks out fine, then any remaining "harshness" is likely normal due to the build properties of the trans, at which point some tuning might help mitigate. But if they find some other issue, the OP might find that the current "clunking/harshness" isn't as bad once this other issue is corrected.

 

The Tq arm bushing was replaced prior to the new transmission. I wouldn’t suspect it was a bushing even if it hadn’t been replaced because it doesn’t make any clunks and nothing is felt in the seat when it shifts at redline. The only time that it does it is under 2k rpm from 2nd to 3rd. The U-joints are the originals (33k miles). But it wasn’t having any clunking or banging in conjunction with a “thud” that was felt under my seat prior to the new transmission & converter going in. The same goes to for the rear end.

The 2nd to 3rd shift at 1,500 rpm isn’t all that “hard” of a shift really. Meaning that it doesn’t throw your head forward like it does from 1st to 2nd at slow speeds. I would almost call the 2nd-3rd shift @ 1,500’ish RPM soft. There isn’t a “shift bump” like there is from 1st to 2nd. I don’t even think you’d feel it if it wasn’t for clunk and the thud that’s felt in the seat. The slow speed 3rd to 4th is also silent and there isn’t a “shift bump.” It’s smoothe engough to where you might not known that it happened if you weren’t watching the tach. The same goes for when the converter locks up in 4th. The clunk from 2nd to 3rd has gotten quieter over time and it doesn’t hit the seat as hard as it did at first. But it was pretty harsh and loud at first. As it is now it’d be tolerable enough if I knew that it was “normal” and that something wasn’t fixing to break.
Maybe it is a normal function of this shift kit since another fella posted that his shifts the same way. If it wasn’t for the shoddy mechanic that did the install, and the VERY loud bang the first time it shifted from 2nd to 3rd I’d be less worried. The not pulling itself at first but now it is is also a little wierd and worrisome. At first I thought that the fluid was low and the dipstick was reading incorrectly. So I added fluid little by little until it started to pull itself. It wasn’t low though, and I actually over-filled it. Once I realized that it was over-filled I drained what was in the pan and filled it back up to the correct level and it was able to pull itself in gear. This was a good while prior before I dropped the pan and changed the filter. So maybe there was a clogg and the two extra qts I poured in unclogged it.

All in all it’s to the point to where “it’s tolerable if it’s normal,” since the thud and clunk have softened up a bit. I’m leaning towards driving it to see what happens, and if it seems like “all is well” I might look into a tune.

I tried to record the clunk with my phone but it didn’t really pick it up to where you could hear it. The guy down the street would’ve heard it the first time that it did it though. 😆

 

kEEP me posted if you have any issues , And i do think a tune would have a dramatic effect on both feel and drivability. The RPM you state for shifts at light throttle seem really really low IMO unless your geared like 373 or something. Of course my own car with 3,08 stock tune and 2800 stall was in 4th by like 35 and i hated that at light throttle. made it feel all mushy like . You could barley tell 3rd and 4th happened except for the slippy feel of the conveter and lockup down low i really didnt like course i have a cam so the lope at low RPM and lockup was not an overly pleasant feel either. .

 

Will do.

It has a 3.23 rear gear and I think it’s usually in 4th gear by around 40 mph or so. It’s always been like that I do believe. It goes into 3rd prior to 20 mph unless I give it enough throttle to where it’ll hold the shift until 2k rpm or so. However, I believe that it shifts a little later when the motor is cold. It doesn’t start clunking until the transmission is up to operating temp. When it is up to operating temp it’ll shift from 2nd to 3rd around 1500 rpm and prior to 20 mph.

 

If you have EFILive or HPTuners,I prefer EFILive you can go into the trans table and adjust some of the trans parameters,That might help before you start taking things apart.Before I went to the Holley Dominator I had the 0411 pcm,My car would bang into gear going from park to drive,I raised the #'s in the force motor current table,Just the upper rows,Shifted nice and smooth after that.Something maybe you can try.

 

Yes if you have a stall even arround 2800 like mine shifting that early which may be find with stock converters as they stall in the 1200 to 1600 range might feel fine and would also hold load on the gear train an upshift that early with stall would basically relax the gear train and IMO makes it more cluncky feeling. Add to that the overun mod when keep all engaged instead of the stock more or less neutral coast and what you feel is quite normal.
In my own car I was not at all pleased with the overall feel of low throttle shifts. To me with the stall even though still shifting at same timing and speeds did feel sloppy well except 1-2 as the low gear nature 3.07 first wound it up a little more so it bumped but the 2-3 felt kind blah and overalll slippy and 4th really worse. Then on as I mentions on mine when warm the TCC would come on in 3rd and 4th at very low speeds and throttle and added another level of clunky and general "yuky feel" . I lliterally fixed it in a single move by raising the low throttle low speed shifts by 20 percent , With 323 would probably go 10 to 15 percent and I moved lockup to 4th only above 40 mph.
I think what you are feeling can best be described is like a manual trans upshifted to early and the back and forth clunk feel as drive train relaxs the grabs.
Honestly if you plan future mods or are not looking to get a full tune or want to learn , Rather than a Tune. I would consider getting HP tuners myself . Most simpler mods you can do easily yourself as its pretty user frendly and cost less than many charge for a full tune. Then you can chose if you wanna learn more, I am learning it myself now, The trans parts and tables as pretty easy. Fuel trims and timing Im not having easy time learning lol. To much math .