A few mechanical questions. Help a guy out
10-14-2008, 11:29 PM
#1
2nd Gear Member
Thread Starter
Join Date: Dec 2006
Location: West Virginia
Posts: 328
A few mechanical questions. Help a guy out
Alright so i brought my automatic 2002 gt a few months ago and I have noticed a few problems.
problem #1. My car will make a clunk from something around the transmission to the rear end only, after putting the car in drive and slowly letting the car move with no gas effort. The clunk is clearly heard and felt. Only one time until i repeat the process. The car also has to be warmed up to hear it. I took it to the Ford Dealership and they checked out the transmission. The transmission came up as fine; although they did mention that the transmission would hesitate at a certain speed. Although they did nothing to solve my problem or diagnose the noise.. What does this hesitating mean? Car is no longer under warranty btw.
Problem #2. The stang only at a certain speed around 38-43 when at a certain speed will shudder back and forth jerking the car a bit. It gives me the impression that it can't decide on what gear it wants and it's just switching gears at a rapid rate on it's own. It's really hard to explain and I wish i was a mechanic so i could diagnose these dumb things without spending an arm and leg on diagnostics.. Again it feels like it's source is from the transmission to the rear end. When I floor it and don't let off i feel the rear end "pop" around 50 mph. now this is a 20-55 mph dash with me flooring it. I'm not sure if that is traction or not..
Problem #3 It seems that if i'm rolling around 28-36 and if i floor it, the mustang has like no power. I get a weak acceleration. No kick or anything. Is this normal? However 20 mph and 40 are very nice. Maybe it's just the gearing? Dumb question, but I thought I'd ask.
But like I said these are weak explanations. If anyone could make any sense of them and help a guy out I would greatly appreciate it. If i had cash flowing out my butt.. I would just replace the driveshaft to the rear end, including all the u-joints, etc. Thanks!
-Chris
problem #1. My car will make a clunk from something around the transmission to the rear end only, after putting the car in drive and slowly letting the car move with no gas effort. The clunk is clearly heard and felt. Only one time until i repeat the process. The car also has to be warmed up to hear it. I took it to the Ford Dealership and they checked out the transmission. The transmission came up as fine; although they did mention that the transmission would hesitate at a certain speed. Although they did nothing to solve my problem or diagnose the noise.. What does this hesitating mean? Car is no longer under warranty btw.
Problem #2. The stang only at a certain speed around 38-43 when at a certain speed will shudder back and forth jerking the car a bit. It gives me the impression that it can't decide on what gear it wants and it's just switching gears at a rapid rate on it's own. It's really hard to explain and I wish i was a mechanic so i could diagnose these dumb things without spending an arm and leg on diagnostics.. Again it feels like it's source is from the transmission to the rear end. When I floor it and don't let off i feel the rear end "pop" around 50 mph. now this is a 20-55 mph dash with me flooring it. I'm not sure if that is traction or not..
Problem #3 It seems that if i'm rolling around 28-36 and if i floor it, the mustang has like no power. I get a weak acceleration. No kick or anything. Is this normal? However 20 mph and 40 are very nice. Maybe it's just the gearing? Dumb question, but I thought I'd ask.
But like I said these are weak explanations. If anyone could make any sense of them and help a guy out I would greatly appreciate it. If i had cash flowing out my butt.. I would just replace the driveshaft to the rear end, including all the u-joints, etc. Thanks!
-Chris
Last edited by Kdaddy; 10-14-2008 at 11:32 PM.
10-15-2008, 01:49 AM
#5
2nd Gear Member
Join Date: Aug 2006
Location: MD
Posts: 492
its probably torque converter shudder . the shudder occurs when the torque converter is locking up . overheating is the main cause , which breaks down the fluid . when TC shudder occurs it will feel like its hesitating & kind of like your driving over rumble strips or something . if this is the case , you will need a new TC . if you want your trans to last you need to get a trans cooler & change the fluid & filter ever 20,000 miles . the clunking is probably like FORD TOUGH said . I am still running stock 4r70w (same trans as you ) w/ modified valve body , Precision Industries TC , trans cooler & a different tune . the 2 things you dont want to do w/ these transmissions are , dont overheat it ( ideal temp is 170*F ) & dont do any WOT shifts into & out of O/D or you will lose O/D .
Last edited by blstoff; 10-15-2008 at 01:55 AM.
10-15-2008, 03:03 AM
#6
3rd Gear Member
Join Date: Apr 2004
Location: Temperance,MI
Posts: 653
blstoff, where did you place your transcooler. Are you running a fan on it ?? ALso, what stall are you running ??
CHimChim, there is a dead spot in my trans too where it won't down shift. Not sure if i's the TC. Mine is locked at all times, did it thru a tune and max the line pressures out
CHimChim, there is a dead spot in my trans too where it won't down shift. Not sure if i's the TC. Mine is locked at all times, did it thru a tune and max the line pressures out
10-15-2008, 04:05 AM
#7
2nd Gear Member
Join Date: Jul 2008
Location: Peoria, IL.
Posts: 262
its probably torque converter shudder . the shudder occurs when the torque converter is locking up . overheating is the main cause , which breaks down the fluid . when TC shudder occurs it will feel like its hesitating & kind of like your driving over rumble strips or something . if this is the case , you will need a new TC . if you want your trans to last you need to get a trans cooler & change the fluid & filter ever 20,000 miles . the clunking is probably like FORD TOUGH said . I am still running stock 4r70w (same trans as you ) w/ modified valve body , Precision Industries TC , trans cooler & a different tune . the 2 things you dont want to do w/ these transmissions are , dont overheat it ( ideal temp is 170*F ) & dont do any WOT shifts into & out of O/D or you will lose O/D .
10-15-2008, 10:50 AM
#8
2nd Gear Member
Thread Starter
Join Date: Dec 2006
Location: West Virginia
Posts: 328
Yeh that does make sense. A Torque Converter might just be it. I'm definitely changing the trans fluid/filter as well as my oil filters in the near future. However i brought the car used at 33k miles and I have a strong feeling the previous owner beat the **** out of it. Examples are power shifting and like you said earlier with the o/d button. I am guilty of it myself, but i stopped doing it a while back. Thanks for the feedback mates. Going to have it looked at it asap.
10-15-2008, 02:21 PM
#9
2nd Gear Member
Join Date: Aug 2006
Location: MD
Posts: 492
blstoff, where did you place your transcooler. Are you running a fan on it ?? ALso, what stall are you running ??
CHimChim, there is a dead spot in my trans too where it won't down shift. Not sure if i's the TC. Mine is locked at all times, did it thru a tune and max the line pressures out
CHimChim, there is a dead spot in my trans too where it won't down shift. Not sure if i's the TC. Mine is locked at all times, did it thru a tune and max the line pressures out
mine stalls to 3500 .
Last edited by blstoff; 10-15-2008 at 03:51 PM.
10-15-2008, 04:09 PM
#10
4th Gear Member
Join Date: Jul 2008
Location: Connecticut
Posts: 1,140
Yeh that does make sense. A Torque Converter might just be it. I'm definitely changing the trans fluid/filter as well as my oil filters in the near future. However i brought the car used at 33k miles and I have a strong feeling the previous owner beat the **** out of it. Examples are power shifting and like you said earlier with the o/d button. I am guilty of it myself, but i stopped doing it a while back. Thanks for the feedback mates. Going to have it looked at it asap.