loud clunk when you put into gear usually means universal joint or joints are going bad, some labor involved but low cost.. u joints connect driveshaft ends to transmission and rear end
Some could be's, Bad u-joints in driveshaft, Bad transmission mount. Transmission cross member loose.
Possibly weak u-joints or transmission mounts
I would first check the u-joints in the driveshaft. But it sounds like the transmission rear mount is broken. CHECK TRANSMISSION MOUNT.
probably something wrong with the transmission like a gear fault or a transmission glitch or overheat. Take it to a repair shop or do some test maitanenence yourself.
could be bad mounts on either the tranny or engine?
most likely the U joint
You need to use the clutch and the shifter smoothly together!
Are you sure it is the transmission that is clunking? It could be the u-joints on the drive shaft that are making the noise. When the u-joints on the drive shaft are bad, there is an audble clunk when you accelerate and when slowing down (basically the same motions you go through when shifting gears).
Could be several reasons and pretty much the same for any vehicle: -Improper replacement -Bad forward universal joint causing vibration at transmission tail -Unbalanced driveshaft causing vibration at transmission tail -Bad transmission mount Universal joints usually "clunk" when bad Unbalanced driveshafts will cause a vibration when driving - the faster the speed the more the vibration
Good news and bad news. It's the upper ball joints, probably lowers need it as well. But there was a recall on the uppers, so if your blazer didn't get serviced in the recall, you can get them for free.
The Transmission needs SERVICED A.S.A.P Hope This Helps.
Just out of curiousity, how is the transmission in this vehicle. Could the transmission be out of sync with the engine? This has happened to me when i had the transmission replaced in a dodge caravan, Good Luck