Tweet
Hey I have a '99 Lumina w/3100 and a 4T60-E.
My transmission makes a "pop" noise when I shift it into / sometimes out of gear. Shifting into R is the most noticeable. Sometimes it won't make the noise merely shifting into D. However most of the time when I accelerate I hear a short "pop" then it seems fine. Usually it won't do it anymore once its in gear but sometimes (more often than not lately) it pops after I take off from a stop sign.
It's been doing this the past two weeks out of nowhere. I don't usually drive it hard, except for one time after doing a seafoam and running it up to about 70 in second and dropping off the throttle in second which I imagine puts some stress on the mounts. Probably fucked something up considering the car has 112K on it. I had the transmission serviced after I was noticing this by my mechanic who I've went to for the past 5 years. I had this done about 20K ago and do this about every 20K with no problem. However I did also notice before the popping the transmission seemed to slip when dropping down to a low gear for highway passing, for example. After the flush, the car now screams. I literally thought I had a 3800 in here, just to give you an idea of how slow the car would actually go. So that was not a good sign. However there were no metal shavings in the pan from now or the last time they did this.
Now, doing my shitty "diagnosis" to give mechanics and shadetree mechs some extra tidbits of info, I was poking around to replicate it the best I could. Here is what I noticed.
When removing upper motor mounts so I can rock the tranny back and forth, there is a "pop" or "click" you hear when the engine comes forwards maybe 10-15 degrees. This is only in park. In neutral, there is no noise.
When the mounts are in place and the gearbox is in P, as you know you can rock the car (duh) and you will hear up to 3-4 clicks from a full "backwards-to-forwards"cycle of just pushing the car.
I got under the car, with the upper mounts in place and would do this on pavement pushing the car forward by using its tire so I could see whats going on. The noise, unfortunately, SEEMS to be coming from the transmission pan. When I grab either driveshaft when I rock the car, I can feel the clicking in them. Both. there is also some side-to-side play, which may be normal, I do not know, both do this too. I probably sound like a retard saying that. However when rocking the car, you can see the engine and trans assembly visibly rock, which seems fine, but hear a popping sound coming from the pan and feel it in the pan and in the driveshafts. I asked that they check the mounts on the trans and motor as well as the CV because sometimes when I turn really slow it pops too. It's a crazy thing and I haven't found anything of much use lately toher than similar conditions blaming things such as inner tie rods and some bushings. No clue.
If you need any more details, please do not hesitate to ask. I know this is long and I appreciate you to take your time and give me your opinion.
My transmission makes a "pop" noise when I shift it into / sometimes out of gear. Shifting into R is the most noticeable. Sometimes it won't make the noise merely shifting into D. However most of the time when I accelerate I hear a short "pop" then it seems fine. Usually it won't do it anymore once its in gear but sometimes (more often than not lately) it pops after I take off from a stop sign.
It's been doing this the past two weeks out of nowhere. I don't usually drive it hard, except for one time after doing a seafoam and running it up to about 70 in second and dropping off the throttle in second which I imagine puts some stress on the mounts. Probably fucked something up considering the car has 112K on it. I had the transmission serviced after I was noticing this by my mechanic who I've went to for the past 5 years. I had this done about 20K ago and do this about every 20K with no problem. However I did also notice before the popping the transmission seemed to slip when dropping down to a low gear for highway passing, for example. After the flush, the car now screams. I literally thought I had a 3800 in here, just to give you an idea of how slow the car would actually go. So that was not a good sign. However there were no metal shavings in the pan from now or the last time they did this.
Now, doing my shitty "diagnosis" to give mechanics and shadetree mechs some extra tidbits of info, I was poking around to replicate it the best I could. Here is what I noticed.
When removing upper motor mounts so I can rock the tranny back and forth, there is a "pop" or "click" you hear when the engine comes forwards maybe 10-15 degrees. This is only in park. In neutral, there is no noise.
When the mounts are in place and the gearbox is in P, as you know you can rock the car (duh) and you will hear up to 3-4 clicks from a full "backwards-to-forwards"cycle of just pushing the car.
I got under the car, with the upper mounts in place and would do this on pavement pushing the car forward by using its tire so I could see whats going on. The noise, unfortunately, SEEMS to be coming from the transmission pan. When I grab either driveshaft when I rock the car, I can feel the clicking in them. Both. there is also some side-to-side play, which may be normal, I do not know, both do this too. I probably sound like a retard saying that. However when rocking the car, you can see the engine and trans assembly visibly rock, which seems fine, but hear a popping sound coming from the pan and feel it in the pan and in the driveshafts. I asked that they check the mounts on the trans and motor as well as the CV because sometimes when I turn really slow it pops too. It's a crazy thing and I haven't found anything of much use lately toher than similar conditions blaming things such as inner tie rods and some bushings. No clue.
If you need any more details, please do not hesitate to ask. I know this is long and I appreciate you to take your time and give me your opinion.
happy driving/racing/cruising
Comment