flogdpup Posted August 30, 2007 Share Posted August 30, 2007 Hi all, I have been a member for some time now and used some great advice from this site. Need some help though with a problem. Two days ago I had the motor mounts and trans mount replaced by a trusted indie mechanic in my area. Since then, when I shift the trans into Drive, the car lurches forward. If you're outside the vehicle when this happens, you can hear an audible clunk noise. The lurch isn't as extreme when the trans is shifted into Reverse, but is still there. At cruising speed the trans shifts but it lags, it's not crisp. When the accelerator is punched, the trans shift is much more pronounced, almost rough. This I know is all very "unlexuslike". I kind of have an idea of what it may be but need some of you pros to help me confirm it. I have taken the car back to my indie mechanic to confirm everything is tight that they replaced. After inspection, he assured me that it was. My theory is that now since the motor and trans are tight, the force of the trans shifting into Drive is now all being exerted on my possibly worn out flexible couplings in the drive line, which are flexing being that they are worn out. Does that sound right on, because the only other thing I could think of it being is a worn out trans or rear differential, which is pretty much unheardof with these vehicles as far as I have researched. Can anyone help me out here or experienced a similar problem after having replaced the motor and trans mounts? By the way, my car is a 94 LS with 140,000 miles. Quote Link to comment Share on other sites More sharing options...
ono8ono Posted August 30, 2007 Share Posted August 30, 2007 I really have no clue of the situation you mentioned. But I have some questions for you if you don't mind. Why you have a motor mounts and trans mount replaced ? What was the systoms before replacing the mounts? I also notice clunk sound when shift to Drive from Park (but NOT from drive to Park); and my shifter is kind of loose while shifting (move left to right). Are these related?Thank you. Quote Link to comment Share on other sites More sharing options...
flogdpup Posted August 31, 2007 Author Share Posted August 31, 2007 I really have no clue of the situation you mentioned. But I have some questions for you if you don't mind.Why you have a motor mounts and trans mount replaced ? What was the systoms before replacing the mounts? I also notice clunk sound when shift to Drive from Park (but NOT from drive to Park); and my shifter is kind of loose while shifting (move left to right). Are these related?Thank you. Is the shifter loose, moving left to right, when you're moving the shifter with your hand, or is the shifter loose when the transmission shifts gears while driving? It sounds to me like the clunk you're experiencing with your car is the same clunk that I am experiencing; when moving the shifter into Drive from Park or Neutral. The reason I changed out the motor and trans mounts is because my transmission kind of lags when it shifts while driving. The shifting is no longer crisp like when I first bought it. I changed the mounts because I knew they were worn from checking them out and was hoping that changing them would improve my transmissions shifting. I also knew from this site that motor mounts last around 100,000 miles before they need changing. Now my thinking is that this has only put more stress on my drive line with possibly worn out flex couplings, but I'm not sure. My car still doesn't shift smoothly, even with new motor and trans mounts. Matter of fact, it now shifts harder when the engine is under more stress than it did before changing the mounts. The lagging has subsided somewhat, but now it shifts harder while driving and clunks/lurches when shifted into Drive. Are you considering changing your mounts? I can explain how to check them out if you'd like. It's pretty simple. Quote Link to comment Share on other sites More sharing options...
LexChamp Posted August 31, 2007 Share Posted August 31, 2007 I really have no clue of the situation you mentioned. But I have some questions for you if you don't mind.Why you have a motor mounts and trans mount replaced ? What was the systoms before replacing the mounts? I also notice clunk sound when shift to Drive from Park (but NOT from drive to Park); and my shifter is kind of loose while shifting (move left to right). Are these related?Thank you. Is the shifter loose, moving left to right, when you're moving the shifter with your hand, or is the shifter loose when the transmission shifts gears while driving? It sounds to me like the clunk you're experiencing with your car is the same clunk that I am experiencing; when moving the shifter into Drive from Park or Neutral. The reason I changed out the motor and trans mounts is because my transmission kind of lags when it shifts while driving. The shifting is no longer crisp like when I first bought it. I changed the mounts because I knew they were worn from checking them out and was hoping that changing them would improve my transmissions shifting. I also knew from this site that motor mounts last around 100,000 miles before they need changing. Now my thinking is that this has only put more stress on my drive line with possibly worn out flex couplings, but I'm not sure. My car still doesn't shift smoothly, even with new motor and trans mounts. Matter of fact, it now shifts harder when the engine is under more stress than it did before changing the mounts. The lagging has subsided somewhat, but now it shifts harder while driving and clunks/lurches when shifted into Drive. Are you considering changing your mounts? I can explain how to check them out if you'd like. It's pretty simple. I had a similar problem with my 95 LS, but it turned out I was low on transmission fluid. Added fluid and the problem stooped. However, I had previously dropped the Trans Pan but used gasket instead of the recommended Toyota sealant. I have a minor leak coming from the side of the pan and the car has again started to hesitate a little when first put in gear. I am going to drop the pan again fix that leak. I am hoping this fixes my problem. Like the other felloe member stated, I no nothing about motor mount and why they need to be change. I'm hoping to learn a little more about the motor mounts Quote Link to comment Share on other sites More sharing options...
ono8ono Posted August 31, 2007 Share Posted August 31, 2007 I really have no clue of the situation you mentioned. But I have some questions for you if you don't mind.Why you have a motor mounts and trans mount replaced ? What was the systoms before replacing the mounts? I also notice clunk sound when shift to Drive from Park (but NOT from drive to Park); and my shifter is kind of loose while shifting (move left to right). Are these related?Thank you. Is the shifter loose, moving left to right, when you're moving the shifter with your hand, or is the shifter loose when the transmission shifts gears while driving? It sounds to me like the clunk you're experiencing with your car is the same clunk that I am experiencing; when moving the shifter into Drive from Park or Neutral. The reason I changed out the motor and trans mounts is because my transmission kind of lags when it shifts while driving. The shifting is no longer crisp like when I first bought it. I changed the mounts because I knew they were worn from checking them out and was hoping that changing them would improve my transmissions shifting. I also knew from this site that motor mounts last around 100,000 miles before they need changing. Now my thinking is that this has only put more stress on my drive line with possibly worn out flex couplings, but I'm not sure. My car still doesn't shift smoothly, even with new motor and trans mounts. Matter of fact, it now shifts harder when the engine is under more stress than it did before changing the mounts. The lagging has subsided somewhat, but now it shifts harder while driving and clunks/lurches when shifted into Drive. Are you considering changing your mounts? I can explain how to check them out if you'd like. It's pretty simple. Is the shifter loose, moving left to right, when you're moving the shifter with your hand, or is the shifter loose when the transmission shifts gears while driving? Thanks for responing. yes, my shifter moving left to right at 'P'; feel like the whole shift is falling apart. Is there something underneath the shifter to hold it firmly? NOT shifter loose when the transmission shifts gears while driving. I don't have any problem with the transmission ; it shifts smoothly at any speed. Sure I would like to check out the mounts, please tell me how. Thank you. Quote Link to comment Share on other sites More sharing options...
Silvia96 Posted September 2, 2007 Share Posted September 2, 2007 I have very similar issues. The car always lurches when shifting into drive, and sometimes when shifting into reverse. The shifter itself is also very loose in the console, the sensation is similar to a loose nut somewhere down in the shifter linkage. I took apart the console, but couldn't see down far enough to locate the problem. The shifter wiggles with about 1/2" of play to the left and right. I also experience some lag when shifting, and some lag, occasionally, when I am cruising and step hard on the gas. It's as though the transmission doesn't know which gear to choose. Also, possibly related, my "O/D off" light flashes from time to time for about 10 minutes at a time. Since the overdrive is part of the transmission, I assume these issues may be related. Any advice? Quote Link to comment Share on other sites More sharing options...
ko90ls Posted September 2, 2007 Share Posted September 2, 2007 My car used to jump when shifting too. Also while driving on the freeway and starting the cruise control the pedal would readjust to the correct position like the linkage was off. turned out to be the case, adjusted my throttle cable and every thing was fine. transmission_servicing_at.pdf Quote Link to comment Share on other sites More sharing options...
ono8ono Posted September 4, 2007 Share Posted September 4, 2007 My car used to jump when shifting too. Also while driving on the freeway and starting the cruise control the pedal would readjust to the correct position like the linkage was off. turned out to be the case, adjusted my throttle cable and every thing was fine. is the loose shifter related to the transmission mount shift lever ? where is the transmission mount shift lever located? any idea? Thank you. Quote Link to comment Share on other sites More sharing options...
glenmore Posted September 4, 2007 Share Posted September 4, 2007 A clunk when shifting from P to D is typically the flex disks. I would just crawl under the car and take a look. I've changed my motor mounts and tranny mount. Tranny mount is easy, motor mounts are a chore. As to a loose shifter, this is common in older Mercedes and the fix is replacing worn out bushings (small plastic delrin) in the shifting linkage under the car. I thought that a slight rattle I had with my Lexus was possibly do to the same bushings so I did the same repair on the Lexus. Turns out the bushing (small rubber, about size of a dime) at 150m was just fine. glenmore 1990 Ls400 1991 300CE 2000 C280 Quote Link to comment Share on other sites More sharing options...
pishta Posted September 5, 2007 Share Posted September 5, 2007 Hi all,I have been a member for some time now and used some great advice from this site. Need some help though with a problem. Two days ago I had the motor mounts and trans mount replaced by a trusted indie mechanic in my area. Since then, when I shift the trans into Drive, the car lurches forward. If you're outside the vehicle when this happens, you can hear an audible clunk noise. The lurch isn't as extreme when the trans is shifted into Reverse, but is still there. At cruising speed the trans shifts but it lags, it's not crisp. When the accelerator is punched, the trans shift is much more pronounced, almost rough. This I know is all very "unlexuslike". I kind of have an idea of what it may be but need some of you pros to help me confirm it. I have taken the car back to my indie mechanic to confirm everything is tight that they replaced. After inspection, he assured me that it was. My theory is that now since the motor and trans are tight, the force of the trans shifting into Drive is now all being exerted on my possibly worn out flexible couplings in the drive line, which are flexing being that they are worn out. Does that sound right on, because the only other thing I could think of it being is a worn out trans or rear differential, which is pretty much unheardof with these vehicles as far as I have researched. Can anyone help me out here or experienced a similar problem after having replaced the motor and trans mounts? By the way, my car is a 94 LS with 140,000 miles. Motor mounts can be checked by this method, 2 people are needed. Start motor and apply heavy brake, rev to 1000 drop into R and have helper watch motor, it should only move about 1/8 inch if at all minus normal torque. Now do D from N the same way. If it really squirms, suspect motor mounts. if they are shot the trans mounts are probably bad too as they are taking all the torque load. CLunking into gear could be a sticking servo or annular piston in the trans, I would get a flush done and pull the negative batt cable for about an hour to reset the trans/ECU memory. Quote Link to comment Share on other sites More sharing options...
flogdpup Posted January 23, 2008 Author Share Posted January 23, 2008 Thought I would end this thread with the cure to my original trans problem. It turned out to be symptoms associated with a cracked EGR pipe. I finally got around to changing my cracked EGR pipe and the new pipe cured all of the trans problems. My LS starts, idles, shifts into drive/reverse, shifts automatically, and accelerates SO smooth and quiet now that I feel like I'm driving a new car. It is completely unbelievable. My suggestion is that if you have even a slightly cracked EGR pipe... fix it! You will be amazed at the problems cured with a new pipe. For the life of me, I can't figure out why the Lexus gods designed such a necessary part to fail. Looking at my cracked one, it was designed to fail. As far as how I changed it... I found where it attaches to the rear of the intake manifold and loosened those two bolts. Then underneath the car I found where it attaches to the passenger side exhaust near the front right oxygen sensor and loosened those two bolts. Next, and this was the butt kicker, underneath the vehicle I was barely able to see and reach the single bolt that supports the center of the EGR pipe. This bolt supports the EGR pipe on the back of the engine block and is a very tight squeeze to reach in between the motor and the firewall. You will be in luck with this if you have small hands and forearms and a long handled wratcheting box end wrench. By the way, has anyone had any experience using the EGR delete plates and if so, what were the effects on your emissions? The EGR pipe is #2 in the pic. Quote Link to comment Share on other sites More sharing options...
Leadfoot Posted January 23, 2008 Share Posted January 23, 2008 Thought I would end this thread with the cure to my original trans problem. Thanks very much for posting the conclusion, it is great when someone takes the time to close off their thread properly. My EGR is badly leaking and I get transmission stubbles often, so that is an excellent clue. Quote Link to comment Share on other sites More sharing options...
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