TC rearend - "grinding" noise

Topic: TC rearend - "grinding" noise (Read 6732 times) previous topic - next topic

TC rearend - "grinding" noise

Reply #15 – August 31, 2009, 12:38:56 PM

So, where did you get this rearend?

TC rearend - "grinding" noise

Reply #16 – August 31, 2009, 09:24:20 PM

Seattle 2 years ago. Came with the complete rearend that was never cracked open prior and all brake stuff for the front, parking brake cables, master cylinder, etc. The differential looked great inside, along with the bearings we took out to replace. The sound is not coming from the differential unless a rapid banging sound can go on inside of it and it can come from one side of the car and not the other.

I've got CHE control arms, new quad shocks, Bilstein shocks, urethane bushings, and calipers that I rebuilt (they were like new as it was, the entire rearend had like 60k (or perhaps it was the item I got that had 35k - who knows anymore). Ujoints have like 5k on them and were fine earlier. Transmission 16k miles now. Engine 2-3k miles. Front suspension/brakes/steering <1k miles. Front springs are new/slightly lower, rear were reused.

If you can figure out the problem within the next week, I'll give you $200 (excluding parts) :p

TC rearend - "grinding" noise

Reply #17 – August 31, 2009, 09:59:14 PM

You know, I might just have to drive up and say Hi! Did you try running it on jackstands with the wheels off or on? To make sure it really is coming from the rear somewhere? Also, does the sound continue when cornering?

TC rearend - "grinding" noise

Reply #18 – August 31, 2009, 10:39:36 PM

We ran it with wheels on. The sound happens during cornering. It's hard to tell if it stops with braking but I will likely have to say no as light to medium braking doesn't do anything. Heavy braking slows down too fast to hear if it continues.

It's fine when cold, after about 5 minutes (excluding stops) it starts to make the repetitive noise at higher speeds. At 10 minutes it begins to be audible below 20mph. When I drove it back from Seattle, it was making the noise continuously when I got into my neighborhood unless I was going <5mph.

Again, it only happens under light to no load. Anything more, the sound is gone. Something with either gets messed up with load or suspension stress/angles. This goes against it making noise on slow smooth roads though. If I had a decent microphone (or any for that matter), I'd try recording it as it's plenty audible.

TC rearend - "grinding" noise

Reply #19 – August 31, 2009, 11:20:19 PM

If you ever drive it by Olympia let me know and we put it up on the hoist. But I don't know what we could find that Ford could not. Are you sure your tires are round and there are no bumps on them? Have you tried to switch the tires from the front to the rear?

I thought too that maybe the lug nuts were loose but I can see where it has been apart many times this can't be.

I also get some weird noises out of my rear brakes sometimes but it hard to hear over the Cadillac engine and I ignore it.

Anyway if you come by maybe two heads will be better than one.

TED

TC rearend - "grinding" noise

Reply #20 – August 31, 2009, 11:37:43 PM

I don't think I ever said Ford themselves looked at it. Anyways, they didn't. I had it at All Ford Performance here in Vancouver and Jeff basically ran out of ideas. I was through Olympia on Friday, but at like 2:30 AM

I seriously don't see how anyone is going to be able to pinpoint it without having a dyno in the air that the car can run on while checking around with a stethoscope. I've had 3 heads in it so far but there's still the chance that we're overlooking something. I talked with the owner at Paragon Auto down in Tualatin and he has access to such a dyno. I can only dream up how much this could potentially cost though.

All I can think of is a faulty caliper, a somewhat-faulty shock, or something loose but I haven't had any luck figure it out yet. I will try ruling out the caliper by applying 50% fluid to the rear and giving it gas while on the brake to see if it goes away.

By the way, how often do you go junkyard scavenging, jrad? I could sure use a couple of those mounts from a rear disc sn95 mustang that hold the parking brake cable away from the wheel (mounted to a swaybar bolt). My zip ties won't last too long. That's the only floppy part but at 5mph, I doubt it would do anything, especially that loud and where it can be felt through the floorpan.

TC rearend - "grinding" noise

Reply #21 – September 01, 2009, 12:09:57 AM

LOL.. Zipties, I love it! Oh well, guess I shouldn't laugh too hard, that's what is directing my fuel line around the motor currently.

So wait, both times you had the rearend up, with the wheels turning and it made no sound? Either it's imbalance/bubble in the tires, or it's in the front.

I drive by Paragon all the time, but I've never stopped there, they look too expensive for me!

Ah, I see what you mean about the "Dyno in the air", basically a dyno built into a lift. I wouldn't think it would be much more than a regular dyno, but then again, I've never put my car on a dyno.

I probably won't be out in a yard for another couple weeks, but maybe this weekend if I get bored. Didn't you need a control cable for the heater mod as well?

This probably doesn't have anything to do with your problems, just very odd;
On the bird, when I get on the brakes, at say, less than 40MPH, I get the oddest grind...grind...grind, sounds like once per tire rev, sound from the rearend like the drums are warped or something, but it has been in storage for a year and a half! You'd think that after 2000 miles it would have fixed itself if it was rust or something.

Also, on my truck, I put a pair of used tires(Almost brand new, I swear) on the front, and around 60MPH, it makes a noise/vibration as if it had a flat spot three times in succession, then waits, and does it again. You would expect it to be constant if it was flat spotted...

TC rearend - "grinding" noise

Reply #22 – September 01, 2009, 12:26:41 AM

On the front we only touched the brake lines and mounted an aluminum overflow tank. With the windows up, it's obvious that the sound is coming from the rear. Until I get down there once more, everything is only going to become speculation. I won't have a chance until Thursday though as I work late tomorrow and have my evening booked on Wednesday. Perhaps I'll come up with something decent to check by then.

I will swap the tires around and run it up without wheels when I get the chance. With the sound though, I 99% doubt either will turn anything up. More of a pain, I have to do this after driving for awhile to get it to the point it acts up again.

TC rearend - "grinding" noise

Reply #23 – September 01, 2009, 01:24:02 AM

Yeah, I hear you about swapping the tires around, I should do it to the truck, but there are six lugs per tire!

Well, hopefully a new piece of information will show up and give us a better idea of what is going on. Let me know when/if you decide to swing down through here, maybe I can meet up with you at the shop.

TC rearend - "grinding" noise

Reply #24 – September 02, 2009, 08:49:41 PM

You know, it may very well NOT be the rearend. I drove it to the store and initially it sounded like it was coming from up front. After I got back, it was loudly coming from the "rear", or so it sounded.

My transmission puked more fluid out the dipstick hole onto my exhaust and that oring was replaced like 2k miles ago. Not a good sign. This first happened when the front brakes were grabbing when the car was test driven once the rearend was in. I hope my transmission isn't messed up somehow - it's got 15-16k miles on it and ran great prior to last week!

The fluid level is still fine and translucent red. No leaks anywhere else. Fluid temperature is 155 degrees. Perhaps I just need to replace the oring after the first incident though.

TC rearend - "grinding" noise

Reply #25 – September 03, 2009, 05:30:21 AM

I once had someone at the store tell me my car was smoking, I look down and see white smoke pouring out from under the car, and it was the trans cooler lines leaking fluid onto the Cat and igniting.

But, I had an exhaust rattle that you would have sworn was coming from the cat, turns out it was the upper end of the air pipe to the Cat was a valve that, since I took out the pump, was just rattling loose in the engine bay.

I also have an odd whistle at around 1200 RPM, It's either the carb, air pipe, or the transmission. I'm gunning for the first two options. :D

I just LOVE project cars...

Was it the same sound?

TC rearend - "grinding" noise

Reply #26 – September 03, 2009, 08:52:30 PM

Yeah so I took it to a drivetrain shop and they don't feel it's any fault of the transmission, rearend, or anything in the rear really. The occasional sloppy shifts when something's clanking around is still making me think of ujoints - specifically the front. Perhaps I should just replace them again - they're cheap enough.

I had to give the usual shpeal about how awesome the car is (I think this guy was the one I last talked to last time also when the trans was leaking out of every orifice and I had them fix it). Apparently shops always think so, being so old but being so new with electronic this and that and brakes that are day and night from standard fox brakes. I did get a "Why did you put a 4r70w in it instead of another aod?! It's basically the same thing!" question last week from a Mustang shop in Federal Way when picking up a speedo gear. I'd agree with the car being great if I had a paint job on it that I was happy with, new seat upholstery, and had my quad TL/TSX projector setup finished for up front. Oh, and if the drivers side seat back wasn't busted on the right side :p

I'm still not sure why my dipstick hole keeps wanting to spit fluid out. I can only assume I need a new oring...again.

TC rearend - "grinding" noise

Reply #27 – September 09, 2009, 08:08:09 PM

I think the sound has gotten worse. I was turning the steering wheel side to side a little bit this morning and a similar, if not identical, sound it coming from just moving the steering wheel back and worth like an inch. It may not be the same but it sounds pretty close. What would cause a "pop" when moving it each direction just a bit? Car running with assist, not pushing it past its small "slop" zone where it begins to be harder to turn the wheel.

TC rearend - "grinding" noise

Reply #28 – September 09, 2009, 08:28:30 PM

Worn tie rod ends will make a pop when you jiggle the wheel back and fourth.

TC rearend - "grinding" noise

Reply #29 – September 09, 2009, 10:28:01 PM

When you did all the rear control arms, you said you had poly bushings, but did you replace the ones in the axle housing with the sphericial bearings?
http://www.summitracing.com/parts/CEE-3168/
I know that I put in all new poly bushings and those bearings and it has made crazy noises ever since, I think mainly from the slop in the bearing and the spacer that it goes in. I imagine that if you didnt put those in, it would be binding pretty bad by what my buddy said after he put all poly bushings in. He said it sounded like his upper control arm boxes were getting ripped out, lol. Mines been getting even louder on deceleration and I think its the tailshaft bushing and slip yoke