Rough shift into reverse

[bdog9seclx]

All other gears shift easily. The truck has sat with minimal driving from the original owner. its a 74. But everytime I shift into reverse it sounds like bad thud and metal on metal. Every other gear is smooth and nothing like reverse. Since I just bought this. Im sure many would recommend getting all the fluids changed on the rear gear transfer case and transmission? oil has been changed. Any other suggestion for just buying it on what to refresh? also vacuum line i read could be part of problem

thanks in advance for the help

Ive read to change the idle. but there is no tach so id be going blind also i am a virgin with a carb. IM a mustang guy with fuel injection knowledge only. But know motors enough to learn...but prob also enough to maybe not do it 100% correctly. Idle is on drivers side of carb correct?

Anyways just thought you guys would be able to help

thanks

 

[BroncoDawg]

Welcome to the Bronco Clunk! Seems to be sloppy and jumps when finally catches up? Mines done that forever and think slop in dana 20 adds to the Clunk. Should do same thing from reverse to drive?

Enjoy your new addiction and welcome.

 

[bdog9seclx]

well only does it from park to reverse really. all others seem fine. ive read it could be vacuum or high idle or ive read ppl adjusted the bands etc but id like to avoid all that. sounds like its common though. Ill say its wierd getting in my wifes yukon when you put it in gear and the truck doesnt even budge or make a noise. these early trucks make you appreciate disc brakes and all other technology lol

 

[bdog9seclx]

looks low on tranny oil will try that! and report back

 

[BRONCONY]

Ours is a 74' also. Isn't is axial wrap? It's always don that

 

[cs_88]

My '74 has always done it as well.

 

[bdog9seclx]

will it be more violent with the hubs locked? it would make sense right since all 4 wheels are engaged and trying to bind or tense up? i freed both hubs and it wasnt as bad as before

 

[Viperwolf1]

will it be more violent with the hubs locked? it would make sense right since all 4 wheels are engaged and trying to bind or tense up? i freed both hubs and it wasnt as bad as before

Usually it's less violent with the hubs locked and tcase in 4WD. Slop in the drivetrain, including bad ujoints or CV, bad slip joint, worn axle gearing, worn tcase parts, worn trans output splines all can contribute to it. High RPM plays a major role. By adding the load of the front shaft you should actually eliminate some of the slop overall if everything is in good shape. If you have a lot of slop in the front drivetrain you won't make the shock any worse than the rear alone.

 

[bdog9seclx]

cool thanks for all the great info

 

[Rustytruck]

Usually with a clank in an automatic then i would pull down the drive shaft and give it a good going over. mine did that and I found a bad journal. better to find it now rather than spit out a driveshaft. I wouldn't have found it without pulling the shaft.

 

[bronco t]

Just a thought, but isn't the reverse gear geared lower than the drive gear, and the torque alone would cause the noise? My 77 pretty much slams in to reverse and slips into drive.

 

[Viperwolf1]

Just a thought, but isn't the reverse gear geared lower than the drive gear, and the torque alone would cause the noise? My 77 pretty much slams in to reverse and slips into drive.

Actually reverse is 2.20:1. 1st is 2.46:1. Hydraulic control pressure is higher in reverse though.