Page 2 of 2 FirstFirst 12
Results 21 to 23 of 23

LS1 Engine Vibration - Worse With New Trans/Driveplate/TC

This is a discussion on LS1 Engine Vibration - Worse With New Trans/Driveplate/TC within the General Help forums, part of the LSx Technical Help Section category; thread from the dead........ this is my story May 2011 - buy flex plate, 2400 stall converter, and 4l60e from ...

  1. #21
    Junior Member
    Join Date
    Mar 2011

    2002 TA

    thread from the dead........ this is my story

    May 2011

    - buy flex plate, 2400 stall converter, and 4l60e from b&m transmissions. install all parts. vibration constant at 2000 rpm, hammers when in higher rpms, car drives like shit. shifts nice though. just vibrates all the time. turn converter all holes on flex plate - no change.

    July 2011

    - get replacement torque converter from b&m. new converter has a balance weight on it. r&i trans with new converter. 2000 rpm shake gone, but still shakes when shifting gears, hammers sometimes, vibration now intermittent depending on how long throttle is held through speed range and what throttle % was through speed range (how fast trans shifts etc.)

    car gets parked for 6 months of winter. still has the issue. figured id deal with it in the spring

    march/april 2012

    - nearing my whits end with b&m. wanted to do first oil change on b&m trans. local parts shop tells me to go down the road to a trans shop. they rebuild converters in house and stock everything i need. i start talking to the guy and we come to an agreement that b&m parts are shit. he recommends i bring down the 2nd converter from b&m and he will check it over for me. remove trans, bring the converter over. he tells me this converter has 0.017" runout on the hub. he recommends i buy a converter from him. $150 from him, half the price of the b&m. give him my stock converter as a core. reinstall trans with his converter and no real difference noted. trans/vibration still acting the same way

    may 2012

    - umi adjustable torque arm finally comes in. u-joint working angles now set correctly. no change in vibration. car drives better with more power being put to the ground. torque arm goes right to the frame so at least there is a benefit
    - install poly engine mounts. definite noticeable change in performance with good engine mounts. old ones were separated from the clam shells. ill tell ya, engine mounts on an 02 f-body are NOT fun to do

    august 2012

    - get all tires rebalanced. huge change in weights. hopefully this will help..... it didnt

    - hardly driving the car as it isnt very fun to drive with this bullshit going on. finally said enough is enough. time to r&i the trans for the fourth time. removed the b&m trans and reinstalled the STOCK transmission (that was having shifting issues 2-3 intermittent and 3-4 all the time. slow shifting problems) with the converter from the local shop. time to go for a drive... NO ISSUES. NO VIBRATION, NO SHIFT POINT VIBRATION, NO JERKY TC CLUTCH SHIFTING. ITS FIXED!!! drive down to work that night and put tools away. total driving time (test drive + drive to work that evening) ~40 minutes of relief. im happy now. except i have the stock trans with an issue installed. hopefully it will last a while

    - leave for work the next morning. get to the on-ramp on to the highway, give it WOT. 3rd gear starts climbing the RPM... trans goes to shift... engine hits the rev-limiter. doesnt go in to gear. wont go in to any gear, r-d-3-2-1. nothing. trans is done. coast down the ramp on to the shoulder of the highway. call ama, get car towed home.

    - pull trans out the next day. more oil than there should have been drains out of the oil pan. remove the trans, converter doesnt have very much oil in it. obviously the oil pump went south.

    - call up local trans shop that sold me the converter the next day. tell him what happened. bring him trans and converter. he farms out the trans rebuild (of the stock trans) and sells me a new converter.

    august 2012 - one week goes by since oil pump grenaded

    - pick up trans and converter. install. shake has returned almost completely similar to the b&m trans. i had the trans shop install an updated sun shell, re clutch it, and put in a mild shift kit. vibration is there, but feels like it might 'wear in' if i drive it a bit. perfect cause im going to take some holidays in a week. put 1500km on the car, something should happen.

    september 2012

    - take holidays. trans eerily similar to b&m trans. 1500km later and im starting to pull my hair out. rebuild a trans and it has issues. this was the stock trans, the stock trans was fine, what could have gone wrong?!?!?


    - put car on blocks and run in gear. shake is there at noted speeds. shifting trans will vibrate and clunk. check driveshaft one more time. no issue with shaft, angles good. twist shaft and clunking noted in trans output section. remove driveshaft and run. no issues because no load on trans.

    - unbolt converter. rpm/converter shake gone (only 1000-1100, and 1800-2000 rpm engine vibration still noted, but very minimal. i know that this vibration exists and it isnt my current issue). turn converter one set of holes. rpm/converter vibration gone. car can rev up in park/neutral now and not shake you out of the seat. obviously the last b&m component that i have installed in the car is a paper weight. flex plate isnt true, but right now its bolted together where the issue is resolved. running in the air the speed vibrations, trans clunk, etc. are still present. put the car down, go for a drive. shift point vibrations are 90% better, 75km/hr vibration is 90% better. tc clutch still jerks the car, and i still get an intermittent tc clutch vibration at highway speed, but i can make it go away by either tapping the brake pedal to kick the tcc out and in or just give enough throttle to cycle the tcc.


    - call trans shop that did the overhaul. let them know what is going on. i was supposed to stop by there this morning so they could put it up in the air and run it. after yesterday and what i accomplished there is no point in running it in the air. there has to be a road load on the drivetrain to make it do anything goofy now. we get to talking and he gives me a tip. suggests i drop the trans pan, remove the accumulator, and check the apc solenoid for an adjustment screw. he thinks his builder may have put an adjustable apc solenoid in when he did the rebuild. so if i take the electrical connector off and there is a torx screw in it, back it off 1/8 turn and see what happens.

    so that is my story. my vibration issue has been related to the transmission replacement i did last year. it is seeming as though, as of today, it has come down to two things. a warped b&m flex plate and trans accumulator pressure being set too high. i will check the apc solenoid this week or the weekend (would be nice to do it over the pit at work instead of putting it on blocking in the garage again).
    Last edited by M-1000; 09-17-2012 at 09:49 AM.

  2. #22
    Junior Member
    Join Date
    Mar 2011

    2002 TA

    Still in the hunt for the source of the issue. It is winter time now so the car is parked and I am thinking about what I can check/repair.

    Going back to September 2012 I also came to notice that the rebuilt stock trans does not hold gears. No matter what position I put the shifter in it will still shift up gears . Local shop obviously messed something up. I've had enough of this rebuilt trans so I pulled it out and put the b&m back in. Its overall operation is better IMO.

    While I had things apart I checked the runout on the converter pads and the flex plate pads. Converter - position 1) 0.000", 2) 0.000", 3) 0.010". Flex Plate 1) 0.000", 2) 0.000", 3) 0.010". 0.020" total runout when components are assembled depending on where I have the converter bolted to the flex plate. Some careful work with the die grinder and a sanding disc brought all 3 mount pads to 0.000". No more runout issues.

    I removed the oil pan from the b&m trans after I got it installed, dropped the accumulator for access to the PCS and tore the separator plate gasket in the process. Dropped the valve body to replace the gaskets and checked things over. No visible cracks or track marks between any of the oil passages, that's good. I did notice that there is what looks to be a pin, maybe 3/8" to 1/2" in diameter, in the case that goes up to the internals at the front of the case. Looks like it is maybe a set pin to hold the forward band in position? Well it isn't in straight it's at a bit of an angle. I'm not sure if that is proper or not.

    Anyway, I did the valve body gaskets, and got reading on the net about the washers (up to 3) being added to the 1-2 accumulator when a shift kit is installed. There were suggestions that for a street run vehicle dont add the washers as it will give harsh 1-2, 2-3 shifts because of the added spring tension on the accumulator. I removed the washer (there was only 1) and backed out the PCS 1/8 to 1/4 turn. Reassembled and drove. NFG. VERY sluggish shifting. Removing the washer from the accumulator did however help to get rid of the shake right before the shift from 1-2 and 2-3. Pulled the pan back off and turned the PCS back up.

    End results for this season of driving/work on the car leaves me with a jerk when the TCC applies between 60 and 80 km/hr. A vibration when driving above 100 km/hr that is intermittent and can be ridden of by cycling the TCC a few times by cycling the brake switch.

    I have been thinking in the past few weeks that maybe it has something to do with the b&m flex plate. Maybe a SFI flex plate is too stiff for my application. Flex plates are supposed to flex, maybe not very much, but maybe not enough in my case that it is allowing the plate to absorb a jerk when the TCC applies. And maybe the flex plate has a slight imbalance to it that is offset by rotating masses when I cycle the brake switch/TCC application position in the converter.

    Since I still have 2-3 months before I can drive the car again I wont have another update for this thread until then. I am thinking I will install the stock flex plate and try things out. I am also going to disassemble the rebuilt stock trans and see what kind of goofy shit is going on inside there. I know there is problem with the manual valve plate, maybe a cut seal or warped body. I will take it right down to nothing and see if there is an out of balance component in the rotating mass.

    If none of this helps me come to a resolution I will deeply consider buying a new stock trans from GM....
    Last edited by M-1000; 01-14-2013 at 10:06 AM.

  3. #23
    Member 01SsRacing's Avatar
    Join Date
    Jan 2011

    2001 camaro SS

    I seem to get something also like this right after installing a poly tranny mount, at 55 I get the on off noice and in third is a pretty strang vib also at idle it seem to be a lil rougher but I was told this was going to happen with the mount being that it has no give.
    2001 Camaro SS, LM 1, BMR LCA, relocation brackets, BMR springs, adj panhard bar, smooth below, lid, sub-frame connectors weld on, strut brace
    2000 WS6, ls6 intake, sub-frame connectors, slp maf, slp cat delete with slp y-pipe, electric cutout, strut brace, smooth below, slp lid, bmr LCA and RLB

Page 2 of 2 FirstFirst 12

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. First Ever: 100% stock LS1 Dyno (hahah!)
    By Teeeman in forum Dyno Information
    Replies: 43
    Last Post: 10-06-2012, 04:14 AM
  2. Chevy Performance Tech Questions - Performance Q&A
    By Ed Blown Vert in forum Camaro / SS
    Replies: 0
    Last Post: 07-24-2008, 07:40 PM
  3. Chevy Performance Tech Questions - Performance Q&A
    By Ed Blown Vert in forum Camaro / SS
    Replies: 0
    Last Post: 07-16-2008, 05:50 PM
  4. Engine Dyno - Build Your First Engine
    By Ed Blown Vert in forum Camaro / SS
    Replies: 0
    Last Post: 12-05-2007, 06:50 PM
  5. 99 Corvette bone stock Complete LS1 Engine 17,000 miles
    By chrisjw1 in forum Parts For Sale / Trade
    Replies: 14
    Last Post: 01-20-2006, 07:39 AM


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts