Vibration/grinding noise

[Randall008]

Hi,
I've got a 1987 Bronco II. It's a 2 wheel drive. It runs and drives well. When I bought the truck. It had a pretty bad grinding noise when I would go from stop at a red light to take off. I figured it was either sticking brakes or the transmission. I checked the brakes, but they looked ok. I had the transmission checked and it was fine. It turned out to be very badly worn cv joints. This took care of most of the issue. However, I still get a similar vibration or shudder if I am stopped, then give it gas turning left or right (usually going up hill). Does anyone have any ideas for what this may be? Thank you in advance.

 

[Curious Hound]

Might want to check your differential for wear. When was it last serviced/inspected/fluid changed?

 

[Randall008]

Thanks for the feedback and advice. Sorry, I should have included this in the post. I had this inspected about 6 months ago by a specialist because I was experiencing the issue I posted about. It was fine

 

[JerryC]

That's tough to say without actually laying hands on, so to speak.
Here's some quick thoughts...
Engine power issue, poor engine output causing the engine to struggle and shaking the vehicle.
Bad motor mount or trans mount moving under load.
Radius arm bushings with excess play.
Bushing play in general, most likely front end.
You said the differential was checked six months ago, it might have developed a problem since then.

 

[broncobuckinaround]

Does it happen in all gears

 

[Randall008]

Thank you for the feedback. I had the differential checked because it was doing this, so I don't think it's the problem. It does not happen in all gears. It is more noticeable when I am turning from a stopped position. It only does it for a second when I first take off. I suppose if I were to say I was looking for a problem that I can also feel it going straight from the stopped position, but it is definitely not pronounced in this instance. I wouldn't be shocked if it was a power issue, or a bushing. The odometer says it's got 45,000 miles on it, so I am guessing it's at least 145,000. The engine runs fairly smooth, but every once in a while there is a slight hiccup, then it goes back to running smooth. There is also a little blow by. I do about half the work myself and the other half goes to the mechanic. I took it to him for this, but he said he couldn't duplicate the problem.

 

[broncobuckinaround]

Automatic or manual. You probably have a cv type driveline. Which you said you replaced. So we can rule that out. Rear dif has been checked. The only thing I can think of is first gear if auto is slipping and if manual the fly wheel is warped

 

[Randall008]

It might be the transmission. It’s automatic. I had this checked as well though. The transmission shop said it was fine. It’s also a brand new rebuilt trans. It was put in about 8000 miles ago, by the previous owners mechanic.

 

[wildbill23c]

Possibly a shudder from the torque converter? Could be a wheel bearing issue causing a shudder too when you load that bearing up during a turn. Its a 2WD, so it wouldn't be too hard to pull the wheels off and check the bearings inner and outer for wear.

Since you had the CV joints repaired already that should rule them out, there's a U-Joint at the rear differential which can cause a terrible vibration when it starts to fail.

At a stop a vibration or shudder could be the engine not running on all 6 cylinders properly, again could be the torque converter....one thing you may try at a stop is shifting to neutral and see if the shudder/vibration goes away, that would lead to a transmission and/or torque converter problem.