Howling

[Whitehorse]

Update: The howling has been fixed with $9.95 worth of posi additive. It hasn't peeped, chirped, squealed, or howled since I put in the additive. Now the only thing howling are the posters at the end of this thread.

Thanks for all the help folks.



Original post:
I have a 95 with 43,300 miles on it. It started howling when I went around corners about 2 years ago. It is only noticible when the temperature outside is between 75F to 85F. Sometimes I'll hear it a little outside that temperature range but between 75F and 85F it's really loud. It only seems to do it with I'm turning a sharp corner. I never hear it while going straight and never when I turn the steering wheel if I'm not moving. I never hear it on the highway.

For the past couple years I thought it was in the front but today with the daughter in the car and the windows rolled down, her and I agreed that it was coming from the rear. It appears to be getting progressively worse. I thought it might be the rear end oil and I just had that changed for the first time. The mechanic told me the oil should be changed every 7500 miles on this vehicle. Is that correct? I've never heard of a vehicle needing the rear end fluid changed that often. I always thought it was 50,000 miles.

I just looked in my manual and it looks like it might be the side and pinion gear in the rear end. If so, where should I take my car in Wichita, Kansas and how much should I expect to be paying?

Thanks in advance.

 

[Whitehorse]

I'm pretty sure I've figured this one out. I think the Dana posi is gone. I've found a replacement for about $350 but I'm wondering if this is something I can attempt in my own garage or if I need to bring it in to professionals. The posi unit I'm purchasing is complete. I'll have to bolt on the ring gear and put it back in. Of course I also need to drop the exhaust and take out the half shafts to get to the posi unit.

Has anyone here done this before? How big a problem am I in for. Is this an afternoon project or weekend project? Would it be better to bring it to the shop? I'm relatively mechanically adept (I'm an electrical engineer) but I've never opened a rear end before and I'll most likely be working alone.

Thanks in advance

 

[G Winter]

Do you know if the posi additive was put in. Without it they can make really strange noises when cornering.

Glenn

 

[Whitehorse]

No. The additive was not put in. I was told that my year (95) didn't take the additive. Were they wrong?

Incidentally, I even mentioned the additive to them and they looked it up and told me I was wrong. I guess that's what I get for going to Jiffy Lube. I have no way to drain the lube in the diff so I went to Jiffy Lube. The rear end was howling before I went there so I can't really blame them for the howling.

 

[Schrade]

If you're gonna' keep the car, get the FSM both volumes off ebay. Even if you don't do the rear end yourself, you'll find it invaluable.

 

[Rabbit]

No. The additive was not put in. I was told that my year (95) didn't take the additive. Were they wrong?

Incidentally, I even mentioned the additive to them and they looked it up and told me I was wrong. I guess that's what I get for going to Jiffy Lube. I have no way to drain the lube in the diff so I went to Jiffy Lube. The rear end was howling before I went there so I can't really blame them for the howling.

Was looking thru the 95 FSM & it refers to a Limited slip additive, 4oz.

It gives the part no. as 1052358.

 

[92BlackVette]

Howling, when referenced to the rear end normally indicates the ring and pinion aren't aligned properly. If there hasn't been any new rear end work, then you typically have carrier bearing wear and you need to look into getting a master rebuild kit for about $180 and have all bearing, seals, rebuilt.

Changing the rear end fluid in a no brainer, but if it doesn't fix the issue go to this link buy the kit and pay for labor only.


YK D44HD - MASTER KIT,MASTER OVERHAUL KIT,INSTALL,INSTALL KIT,INSTALLATION KIT,KIT,TIMKEN,TIMKEN BEARINGS,DANA,DANA SPICER,DANA SPICER,OVERHAUL KIT,YUKON,SPICER,SEAL,DANA 44,DIFFERENTIAL,SPICER 44,JEEP,SHIM - Yukon Master Overhaul Kit for Dana Spicer

 

[Whitehorse]

Thanks everyone.

92BlackVette,

That's what my FSM pointed to (see my original post). I looked into it more and realized I could rebuild or replace the posi unit. I don't think I want to attempt to rebuild it as I've never done this before. A mistake would mean taking everything apart again and I don't want to go there. That is why I finally asked about replacing the posi with a rebuilt (about $350). I'm assuming replacing the posi with a rebuilt is a much easier task than rebuilding one.

My remaining questions for those who've done this many times are:
1) Is it something I'm better off letting a pro do being as I've never done this before and I won't have help?:bash
2) Is this going to take me a day, weekend, two or 3 weekends?;help
3) Are there any gotchas not covered in the manual that the experienced can clue me in on before I dig a hole for myself?:W


Schrade,

I purchased the manuals when I bought the car. I try to do as much work on my cars as possible. I just responded to G Winter's post before I trudged downstairs to pull out the manual again. I had already resigned to replacing the posi (as indicated by the manual) when I wrote the second post.

Thanks again all.

 

[tonyponykay]

43,400 miles ?

how does a rear end wear out with that many miles on it?:confused

I'd be checking a lot of other things first before I accepted this diagnosis. things like the tire carrier even, bearings, even tires can cause a wierd noise sometimes.

I duno, maybe rear ends wear out that fast, but i've had 5 vettes over the years and never had a rear end wear out in any of them. (yikes, quick knock on wood) <----- beats a fist against his noggin.

anyway, good luck, I wouldn't be a good enough mechanic to answer your question about doing it myself, but I sure would make absolutely sure that it is the rear end and not something else. :confused

you might want to add the gm additive, call the dealership and ask them about it, NOT JIffy Lube.. never take your car to Jiffy Lube.. never ever ever.. they ruin cars... leave drain plugs off, put in used oil, all kinds of horror stories... I've heard and even experienced myself.

used to take my car there until I noticed what kind of people were working there. I usually print out a sheet of what I want done if I take a car to anywhere, even for an oil change because during that oil change i want my ball joints lubed etc.. and my differential fluid checked and maintained properly.

these guys don't even bother reading what you write, perhaps they can't read, I don't know. But I watched them do none of what I had written other than just change the oil, check my air filter and put the air filter cannister's cap back on wrong, which later on I had to fix because they broke the strap and screw (was on a dodge truck, heaven knows I'd never take a vette to them). Had F-body in Baltimore once even break my intake tube ($110) and put some goop on it and tell me it was fine...

I was in such a hurry to get my car out of their incompetent worthless hands, I didn't care, I took it home and from then on, did everything myself.

I'd almost bet that your differential has no problem with only 43k on it. I'd be looking elsewhere, jack rear end up, (be safe) and turn car on, in gear, let wheels spin, have someone in the car for safety. Listen and check everything.

good luck

tk

 

[92BlackVette]

how does a rear end wear out with that many miles on it?:confused

I'd be checking a lot of other things first before I accepted this diagnosis. things like the tire carrier even, bearings, even tires can cause a wierd noise sometimes.

I duno, maybe rear ends wear out that fast, but i've had 5 vettes over the years and never had a rear end wear out in any of them. (yikes, quick knock on wood) <----- beats a fist against his noggin.

anyway, good luck, I wouldn't be a good enough mechanic to answer your question about doing it myself, but I sure would make absolutely sure that it is the rear end and not something else. :confused

you might want to add the gm additive, call the dealership and ask them about it, NOT JIffy Lube.. never take your car to Jiffy Lube.. never ever ever.. they ruin cars... leave drain plugs off, put in used oil, all kinds of horror stories... I've heard and even experienced myself.

used to take my car there until I noticed what kind of people were working there. I usually print out a sheet of what I want done if I take a car to anywhere, even for an oil change because during that oil change i want my ball joints lubed etc.. and my differential fluid checked and maintained properly.

these guys don't even bother reading what you write, perhaps they can't read, I don't know. But I watched them do none of what I had written other than just change the oil, check my air filter and put the air filter cannister's cap back on wrong, which later on I had to fix because they broke the strap and screw (was on a dodge truck, heaven knows I'd never take a vette to them). Had F-body in Baltimore once even break my intake tube ($110) and put some goop on it and tell me it was fine...

I was in such a hurry to get my car out of their incompetent worthless hands, I didn't care, I took it home and from then on, did everything myself.

I'd almost bet that your differential has no problem with only 43k on it. I'd be looking elsewhere, jack rear end up, (be safe) and turn car on, in gear, let wheels spin, have someone in the car for safety. Listen and check everything.

good luck

tk

This is true, and there are a lot of times where howling is actually something else in the drive train.

 

[Whitehorse]

how does a rear end wear out with that many miles on it?:confused

I'd be checking a lot of other things first before I accepted this diagnosis. things like the tire carrier even, bearings, even tires can cause a wierd noise sometimes.

I duno, maybe rear ends wear out that fast, but i've had 5 vettes over the years and never had a rear end wear out in any of them. (yikes, quick knock on wood) <----- beats a fist against his noggin.

It's not likely it is worn out. It's more likely a faulty part to begin with. Could be some contamination got into the oil at some point or a defective gear or bearing. I see it sometimes in new parts in aerospace.

It's definitely coming from the back of the car and only howls when I turn a sharp corner (left or right). It never makes a sound going straight or on a mild turn. It also appears to be temperature sensitive. Above 80 degrees it howls a lot more than when the temp is lower. The only thing I can think of that only moves when you turn a corner is the posi unit. It has to be the posi.

I know Jiffy Lube is no place to take my car but I usually do all the work myself and I have no way to get the old fluid out of the diff and no way to pump lube back in. It was still a quick and cheap way to find out if lube was the issue. It wasn't. Next time I'll take it to Firestone and wait half the day. Of course, if I replace the posi by myself I'm going to have to find a way to get some oil back in there. Firestone is only 2 miles down the road but still...

 

[tonyponykay]

well i hope you find it

I certainly don't have experience enough to tell anything for certain, however, not positive those symptoms point to anything in the differential.

going around a corner and howling... I'd be careful and make sure. I'm certainly no expert but sounds more like bearings or something drivetrain, rear axle etc than the differential which I can't imagine how turning a curve could affect it and make it howl.

Like I say, I'm no expert. I'd ask around a lot, check bearings, wheels, tires,

i'll tell you, on my 87, previous owner stuck wrong wheels on it, some riken wheels that set too far out and everytime i turn my wheel to the right and back up, the tire hits the wheel well and howls and moans like a pregnant cow.

got a squeak or something too cornering especially, but I am sure it in the wheels, balljoints etc.

I wish you luck and hope you find the problem. If anything, I'd find a way to switch out the fluid in the differential, that is if you serious, and put in new fluid and additive and see if there is any change in the howling. If there IS change, and the howling is better or worse, you maybe correct in diagnosis. However, if there is NO change, then I would think your problem lies elsewhere..

that is a lot cheaper and easier than taking and changing it all out. at least test the theory first. Anyway, its an idea.

good luck


tk

 

[John Robinson]

Changing fluid

I went to Harbor Freight and bought what looked like a large turkey baster to pull the oil out of the diff. Bought the fluids at Advance Auto. Its a little messy but can be done this way.

 

[Whitehorse]

I went to Harbor Freight and bought what looked like a large turkey baster to pull the oil out of the diff. Bought the fluids at Advance Auto. Its a little messy but can be done this way.

Thanks! My wife just happens to work at Harbor Freight and I know what you're referring to. I'll pick one of those up so I can change it the next time.

 

[John Robinson]

Thanks! My wife just happens to work at Harbor Freight and I know what you're referring to. I'll pick one of those up so I can change it the next time.

Since you have had the fluid changed you only have to pull out enough to be able to put about 8 to 16 oz. of posi lub in.

 

[LT4man]

Positraction lube is used to lubricate the clutch packs in a posi unit. Without this very important lubricant, you will get noise/howling when attempting any kind of turn: left or right.

Put additive in as John Robinson instructs and you will good to go!

Every Vette made with a positraction differential uses the posi lube.

AFTER QUIETING DOWN YOUR DIFF, PLEASE BE SURE TO SAVE THE !

 

[Whitehorse]

Thanks LT4man. I hope that's all it is. I just jacked up the car to put in the posi lube and I don't have a torx big enough. My set stops just below the needed one. Arrgghhh!!!

While I was under there I studied what it is going to take to drop this diff and it's definitely more than a weekend job for me. I doubt I have all the tools and I doubt I have the memory anymore to remember how it all goes back together. It's a pretty complicated looking setup back there. It's time to go search out a local Corvette club with a resident pro. I just pulled out the manual and it's going to probably cost me as much for special tools to do this rear end work as it would to pay Chevy to just replace the posi unit. Yeow! I sure hope that this is only posi fluid causing the problem.

I guess I'll stop by Sears this week and see if they have a larger torx set. I also need to find a syringe. The turkey baster thing will do well for getting the lube out but it won't help for putting in 4 ounces of posi additive. I have to squirt uphill and I doubt I can empty that turkey baster thing uphill.

I find it interesting that the plug is at the bottom (on the side)? It doesn't look like I can put much lube in this rear end before it's going to start coming out the side.

 

[gmjunkie]

Thanks LT4man. I hope that's all it is. I just jacked up the car to put in the posi lube and I don't have a torx big enough. My set stops just below the needed one. Arrgghhh!!!

While I was under there I studied what it is going to take to drop this diff and it's definitely more than a weekend job for me. I doubt I have all the tools and I doubt I have the memory anymore to remember how it all goes back together. It's a pretty complicated looking setup back there. It's time to go search out a local Corvette club with a resident pro. I just pulled out the manual and it's going to probably cost me as much for special tools to do this rear end work as it would to pay Chevy to just replace the posi unit. Yeow! I sure hope that this is only posi fluid causing the problem.

I guess I'll stop by Sears this week and see if they have a larger torx set. I also need to find a syringe. The turkey baster thing will do well for getting the lube out but it won't help for putting in 4 ounces of posi additive. I have to squirt uphill and I doubt I can empty that turkey baster thing uphill.

I find it interesting that the plug is at the bottom (on the side)? It doesn't look like I can put much lube in this rear end before it's going to start coming out the side.

I use a small funnel and a long rubber hose over the wheel and out the top of the wheel opening!!

 

[Whitehorse]

Excellent! A small funnel I have. Perhaps the hose from the turkey baster thing will fit onto the funnel. Tomorrow I go shopping. Does anyone know what size torx I need? I could always just buy the next bigger set. I think my biggest one is about 1/4". I think the size needed is either 5/16" or 3/8". That's if it's not metric.

 

[John Robinson]

I use a small funnel and a long rubber hose over the wheel and out the top of the wheel opening!!

Oh ya I forgot when I did mine I jacked it up and removed the right wheel and inner fender and had a straight shot at the hole to fill. Why did I not think of using a funnel and going over the wheel lot less work. Because I am not the Junk and only he knows how to make it easy.:bowrofl