Hey everyone,

I'm getting ready to drive\move 1400 miles and I'm bringing my f150 up to the task. She runs great, I'm having some issues with down shifting...but I'll get to that. I flushed my AOD about 3 months ago, and recently added another tranny cooler\remote filter. Tonight one of the hoses blew off of the remote filter and I lost about 3.5 quarts of fluid. I fixed it and made sure the hose wouldn't come off, refilled the tranny, and it hasn't seemed to effect anything. Money is tight so I'm trying to make sure I replace what the problem is. Anyway, there's some noises I'm trying to take care of...

1.) A front end, passenger side creak when the engine is under load. The creak gets worse depending on how much gas I give it. It's worse when it's cold, once it's heated up I can only get a slight creak when I gun it. I'm thinking motor mount?

2.) When I brake somewhat hard, right before I actually come to a stop, I have a rear-end rumble. At first I thought it was U-joints, but those have already been replaced. I think its the transmission somehow, because if I put it in Neutral, the noise is gone. Another reason I think it's the transmission is because it seems to be right when it downshifts(into first?) that the noise happens. On top of this possibly being a shifting problem, it seems that lately I have to give her more gas to make it down shift. For example, when I pull up to a red light and it changes to green when I'm going ~30; it seems I have to put it half way down to get anything to happen. I'm thinking it's TV adjustment causing this entire problem, and no matter what I do I can't get it right. I've followed Haynes, the youtube video about just taking the slack off the cable, the other website about using a 5/16 bolt to mark it, etc. I'm running out of ways to mark this thing.

As far as the brakes are concerned, I also just put a f350 M\C and booster on, along with a full flush. 3 months ago, all fluids were flushed, oil (which I've since done again), tranny, rear-end, radiator, etc. (no transfer case...2wd). Power steering was flushed when I did the saginaw swap, new fuel pumps\strainers\sending units at the same time. Is there anything else I should be doing\looking for to be ready for this trip?

 

Bump? Is there some checklist I should go through before I drive this far?

 

Just some ideas.

About the noise with the engine .... "creaking", sure it's not a belt or alt bearing? Might get a trusted buddy to apply some load to it in gear while you stand to the side looking at the engine on the pass side. Not a long load, not a hard load, but enough to see what's going on under trhe hood maybe?

About the rumble on slow down, my '77 has a grease fitting to shoot grease into the slip joint of the drive shaft back behind the carrier bearing. Look at the splines there and then jack the trucck up and have a buddy turn a rear wheel and you take a wooden stick or stethascope and listen to the bearing by laying it against your ear and the bearing.

You can also use that stick beside the ear and placed against non moving parts like alternators to listen to bearings, etc.

Be careful.

 

Thanks for the reply, I've listened to the whole motor with a stethescope (for other reasons) and I know the sound isn't coming from there anything on the pulleys, etc. Do you know which way the motor leans when it's in gear\under load? If it leans towards the driver side, it's gotta be the motor mount.
I read for hours and hours about trying to grease the slip joints, when my axle only has a spline at the front end (that goes into the tranny). I decided not to grease it because the grease would get mixed with tranny fluid, which I assume would not be good. The rumble is still there, but I think I was able to get the TV cable adjusted correctly, I drove it today and yesterday with normal, quiet shifts (other than the typical aod clunks). I'm taking it down to discount tomorrow to have them double check the balancing, we'll see if that changes anything...

 

Under power against a load the engine willl try to rock over onto the right (passenger) side and pick up off the left (driver) side mount.

OH, OK, that's why I mentioned carrier bearing. Two piece rear drive shafts have a spline slip joint AND a carrier bearing. Your's is a one piece and has neither so it's NOT that as the yoke slipping in the trans gets some lube by trans.

You've checked rear end lube level and you are sure the nut holding the rear yoke on the rear end is not backed off? I mention the nut, it would have no reasion to be backed off unless like a rear pinion seal was replaced ...,
... but if it ever was and was now loose ...
... then on coast down against compression like when the trans drops into 1st would tend to pull the pinion back to the rear and will cause gear noise sounding like a rumble.

If it was loose, you want to be very careful tightening it up. I would NOT torque it back all the way to spec as you run the very real risk of crushing the sleeve more which you do NOT want to do. I'ld lock tite it (using locktite) really good and tight, maybe 100 ft pounds at most, then I might even stake it once or twice.

There is a proper procedure to fix it but if loose, you've lost the starting point.

 

I've changd the rear end fluid with Lucas, and it is a limited slip. I havn't had any leaks but ai will double check the level, as well as that nut. Thanks for the ideas, OI'll let you know the outcome.

 

Did you add any friction modifyer when you changed the rear diff oil? I think all LS diffs need some.

 

I didn't because the Lucas Oil said it included it. I tried adding some and it got better, but was still there. Last night I flushed the rear end again but put Royal Purple in there, and it is MUCH better, if not totally gone. I'm moving tomorrow, but the drive is actually going to happen starting Wednesday. Right now it rides relatively good until 65 mph, where it vibrates like crazy. I'm taking it to Discount Tire again tomorrow morning (third time) to have them balance the tires again, as well as the alignment guy to make sure all is within spec.

Here's some pics of the rear-end: