Need help, can't figure it out

[Billybronco2]

So, I have a 1988 Bronco2 2.9 5 speed manual. Now here's my problem. I get a grinding/binding sound out of my truck when I make left turns. It's not a suspension problem because it will do the samething when I pull the left side up on a curb and the vehicle isn't moving. Also, occasionally it sounds as if the tranny is hitting the floor board. I replaced the tranny mount and it still does it. When driving strait down the road it runs like a champ. Its just left turns that it sounds like something is binding. If you have heard of this befor or have any idea what is causing this please let me know. I'm getting to the end of my rope.

 

[RonD]

Front axle, manual or auto hubs?

 

[Rowdy Fitzgerald]

4x4 or 2wd?
When was the last time the bearings were greased?
Is it possible the tire rubbing the back of the fender?

 

[Lil-Pony]

If its 4x4 your hubs could be engaged causing this sound as you drive. Try it on a softer medium like lose dirt or sand and see if the sound is still made

 

[wildbill23c]

His profile states its a 2WD model, so the 4WD system isn't even there to cause binding problems LOL.

Sounds like it possibly could be a shock that has failed and causing the noise, or a mount broke as well.

 

[RonD]

Oops, missed that 2WD part.

Could be differential binding up, that could cause trans to lift.
Check the door label to see what axle you have, if limited slip then could need some additive or fluid change with additive.

Going around a corner means the axles/wheels need to turn at different speeds, this is when a differential issue usually shows itself

 

[Billybronco2]

But wouldn't the diff make noise making both left and right turns if that was the problem? And as stated above it does it when i park it on a curb and its not moving. Rules out the diff i believe. When i hear /feel the noise when its not moving makes me rule out and thing suspension related or rear diff related. Its is something taking place with the tranny or motor. Motor mounts maybe I don't know.

 

[RonD]

no, not necessarily.

It could be end play or gearing on one axle that is the problem, so only binds when axle is sliding out, or when axle speed is higher or lower than the other axle, it could just be higher or lower only not both.

I would jack up the back and check end play on both axles, Fords do have some normally, 1/4"-1/2", more than that would be a concern, even 1/2" could be the start of an issue.
End play is from the C-clips that hold the axles inside the differential, they can start to wear and eventually fail, axle will come out while driving down the road, not a good thing.
Usually this would produce a clunking sound when cornering as axle slides out slightly then comes back in when straightened out, not a binding issue.
I would think side gear wear could cause a binding on one axle.
If possible I would drain the fluid and watch it for metal filings.
Drive around to warm up the oil then drain from the bottom, check for metal, clean off gasket and refill with the old oil if no filings are seen, add some Limited slip oil if needed on your model.

Driving a limited slip differential without the limited slip oil in it will make you think the rear end is going to drop out, lol, so it is very important to have that in there if it is a limited slip differential.
I bought a corvette once that had "a rear end problem", guy had changed rear end oil but didn't put in the additive, started binding going around corners, I got it cheap, expected to put in a new rear end, but all it needed was the additive