jshea Posted October 18, 2005 Share Posted October 18, 2005 ok so im going down the road and my car shifts gears normally then at about 2000 RPM's it drops to about 1500 and the car shakes a little and the needle wont move until my foot is almost down to the floor and then it jumps back up. My pathy does this constantly and its really annoying? it seems to me that it might be my tranny slipping but im not sure if anyone knows or if this has happened to them any help would be appreciated thanks Link to comment Share on other sites More sharing options...
derogate Posted October 18, 2005 Share Posted October 18, 2005 (edited) Milage? Which gear does it do it in and at what speed? is it shaking like its gonna stall? or Is it a vibration/shudder kind of shake be descriptive. Edited October 18, 2005 by derogate Link to comment Share on other sites More sharing options...
MaritimeMan Posted October 19, 2005 Share Posted October 19, 2005 Manual or auto? Link to comment Share on other sites More sharing options...
Slick Posted October 19, 2005 Share Posted October 19, 2005 does it slow down wneh the rpm's are down or is speed maintained throughout? Link to comment Share on other sites More sharing options...
denisb Posted October 19, 2005 Share Posted October 19, 2005 First off I am not a Tranny expert and if anyone wants to corect or add to this do jump in. Secondly I'm assuming this to be an auto tranny. Kinda sounds like a tranny chater at torque lock up. As soon as you hit a cruising constant speed, your torque converter will lock up (less wear within the torque, kinda the same idea as your clutch not being let out all the way on a manual). The chater is due to the clutches in the torque not grabbing properly (in laymens terms). This could be due to poor fluid presure or dirty fluids. A tranny oil change might help. I recomend replacing the screen also, but different people have different opinion on this. As for the difference in RPMs: When you accelerate, the torque will then unlock to alow your rig to reach higher RPMs and therefore higher torque. This is when your RPMs are going up. The 2000 to 1500 RPMs sound about right at highway speeds. If this is your issue, you will also notice that in town (aprox. 30 Mph) you will also get this chatter as soon as you reach your cruising speed, then if you tap the accelerator just a little your rig will jump up in RPM. Hope this helps, Denis Link to comment Share on other sites More sharing options...
jshea Posted October 20, 2005 Author Share Posted October 20, 2005 thanks for your help denis and as for everyone else's questions my pathy is a 94 with 113,000 miles and automatic tranny and umm it does it at basically all speeds its more like a vibrate than anything else and ummm i think it might have something to do with putting the glasspack on? could that be it thanks Link to comment Share on other sites More sharing options...
denisb Posted October 20, 2005 Share Posted October 20, 2005 (edited) Just for an FYI a tranny chater does feel like if you are running over a rumble strip. It might of got more noticable when you put your glass pack on due to the louder exhaust. I noticed my torque locking up more when my Y-pipe gascket let go(because the louder exhaust emphasised the difference in RPM)......actualy that's when I noticed and started asking the same questions you're asking now. One more question, does it "vibrate" constantly? or does it "vibrate" for 1/4 mile or so as it drops in RPM and then go away? Denis Edited October 20, 2005 by denisb Link to comment Share on other sites More sharing options...
ibstillaweiner Posted October 20, 2005 Share Posted October 20, 2005 good reply denis. seems you have knowlesge on the trannies.... well its a 94 auto a? seems the overdrive and lockup is where you have an internal issue, the chatter is probably (more likely) coming from the tq converter as well. i think. but im not that experienced with the re rannies, ive rebuilt mine myself twice.... kindo keep in mind if you use process of elimination, you can help narrow down the problems. now you have a few problems. change in rpm with no spped difference... how fast are you going with this happens..... your exhaust doesnt make that noise does it???? not sure myself cause im not there to check it out. i wish i could be more help... :help: Link to comment Share on other sites More sharing options...
jshea Posted October 20, 2005 Author Share Posted October 20, 2005 its really a pest because whenever i get to around 2,000 rpm it drops down and stays there and then vibrates and slows down until i put my foot down almost to the floor so basically i cant just cruise along at 2000 rpm's or it will drop like i said and it does this at all speeds thanks again for the help and im not to familar with tranny's so all these "chater lock ups" and stuff like that im not to sure what it means i just wanna find away to fix it but hey im using this as a learning experience so thanks Link to comment Share on other sites More sharing options...
jshea Posted October 20, 2005 Author Share Posted October 20, 2005 o yea and denis it will constantly ivbrate and stay at low rpm's until i put my foot down on the accelerator Link to comment Share on other sites More sharing options...
Filthy Luker Posted October 21, 2005 Share Posted October 21, 2005 What does the fluid look like? Link to comment Share on other sites More sharing options...
denisb Posted October 21, 2005 Share Posted October 21, 2005 Although it's hard to say without a test drive, I would be suspicious about your torque converter. Since it seems to act up when your torque actually locks up and and when it unlocks (when you step on the accelerator) it seems to be fine. You can bring it to a tranny shop for a test drive, they might be able to give you more insight. However keep an open mind when they give you their thoughts. Here's why: I brought mine in and it had a tranny chatter. They told me that if a tranny conditioner didn't help the torque had to be replaced and the tranny rebuilt ($2200 to $2500). I tried the conditioner and it helped but didn't solve the problem. About 6 months later the tranny stoped (No gears). A mechanic friend of mine helped me take the pan off and said that there was no excessive debris in the pan so.....I decided that for the $100 it was going to cost for gasket, oil and filter screen, I was going to try a tranny oil change first. .I have since probably put 10K miles on the tranny with no problems and the chatter dissapeared as soon as I did the oil change. If you decide to try a tranny oil change, check the pan for shinny metal shavings. The metal shavings are usually a sign of torque converter wear. Good luck! Denis Link to comment Share on other sites More sharing options...
vidro Posted October 21, 2005 Share Posted October 21, 2005 If I could interject a very novice opinion. Do to my over whelming amount of post regarding my own problems most know I'm not an expert on Pathies. If your vehicle were carbureted I would say you had a "float" problem, clogged jets or something more fuel/spark related. What made you first think it was a trannie isse? You mentioned putting a glass pack on, did you mess with the oxygen sensor? Did you cut out the other muffler? I'm just throwing out some stuff, may not even be worth considering. Link to comment Share on other sites More sharing options...
denisb Posted October 21, 2005 Share Posted October 21, 2005 (edited) vidro, you have a valid point. His rig is a 94 looking at his member info so it leaves out the float problem. I am going by the disscription of the problem given in writing. Without a test drive, it can sound like one problem and be something totaly different. In my opinion this sounds tranny/torque related, but a test drive by a competent mechanic would definately help you in your diagnostics. Denis Edited October 21, 2005 by denisb Link to comment Share on other sites More sharing options...
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