2003 LX. 265K miles. I notice that besides the common thunk that I feel when I let off the gas to coast and then re-apply throttle, there appear to be thunks when she downshifts when I'm slowing down for a stop sign or a red light. Not intolerable but noticeable. The fluid looks clear red at the dipstick, and doesn't appear to smell burnt. Wondering if this is all part of the same problem with a diff bushing or something, or is this a sign of a very worn transmission?
Transmission Thunk (1 Viewer)
- Thread starter GremlinMobile
- Start date
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Lay under your front and have someone else shift from P to D to R and watch your front diff. If it's moving up/ down when shifting your diff bushings are bad.
In addition your front drive shafts flanges might be worn out.
Lots of threads on those two topics in the forum.
After I replaced those parts I didn't have any thunks left.
In addition your front drive shafts flanges might be worn out.
Lots of threads on those two topics in the forum.
After I replaced those parts I didn't have any thunks left.
I know a lot of folks have complete trust in their brakes, and whoever is doing the shifting, but if possible please find a safer way of looking at the diff other than laying under a running vehicle while someone puts it in gear. You can prop a mirror on a rock and watch from the side, or lay your phone under it and get video, or convince a neighbor you don't like.
- Thread starter
- #4
Thank you both for the advice. To clarify, you're suggesting that the thunk that I feel when the transmission is down-shifting is still likely due to the drive flanges and/or diff bushings? My old land cruiser had the typical thunk but the tranny shifted up and down smoothly, that's why I'm wondering if there is something loose that is attributable to the transmission specifically here.
Main thing I suggest: before digging deep invest 10min while standing and see if anything is moving that isn't supposed to move/ that nothing is worn out that you might see from the outside.
Once confirmed that all visuals are good I guess the pro mechanics and transmissions lovers will have many more ideas
But first I'd check the typical suspects. As long as that didn't happen I guess people will always have that "bad taste"
Once confirmed that all visuals are good I guess the pro mechanics and transmissions lovers will have many more ideas
But first I'd check the typical suspects. As long as that didn't happen I guess people will always have that "bad taste"
I watched a youtube video about the front brakes and they mentioned that the thunk could be coming from the old flanges which can be replaced for about 40$. Some other videos indicated that the drive shaft just needed to be regreased. I would assume its a combination of both.
I disagree and in my experience, the clunk you feel when coming to a stop is related to drive shaft grease, specifically the slip joint or whatever it's called. I feel this every now and then and it's remedied by greasing.
This is not to be confused with a different clunk being felt when shifting out of gears or coasting from highway speed, that usually relates more to CVs, bushings, etc. I also had these clunks and it is easily noticeable by looking under the vehicle where the axle meets the hub and have someone shift through gears, check for play.
Always start simple, first step is to ensure all of your grease fittings are passing grease and everything is lubricated. Then you can start thinking about CV / front end play. If all that checks out then you can think about transmission problems or whatever else is further along in troubleshooting.
