Howling

[John Robinson]

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.

I don't know on the 95 but on my 93 I am pretty sure it was a metric allen wrench not an American standard allen wrench

 

[LT4man]

I believe the size of the tool is 17mm in a hex allen head.

I use a small pump which attaches to the end of my 3/8" electric drill. This pump has a hose on both ends. One for the differential and one going into a drain pan. I jack up the Vette at all four corners to maintain a level position. I do not remove anything but the plug in the side of the differential. About 5-10 minutes of pumping (drilling?) and all the fluid is in the pan.

I bought a hand pump at Autozone(?) which attaches to the top of a qt plastic container. I put the gear oil (I use synthetic 75/90 wt) in that qt container along with the additive. Very easy to use the hand pump under the Vette.

If you just want to add the additive, just take out a small amount of gear oil. I would use two (2) bottles of the additive. 4oz + 4oz = 8oz. A much older transmission expert told me that many years ago. That way you are sure to get at least the 4oz required into the differential.

Put gear oil in until it just starts to come out the fill hole.

You will be good to go!

AFTER ADDING YOUR POSI LUBE, BE SURE TO SAVE THE !

 

[Whitehorse]

Thanks LT4man.

I just assumed it was a torx because everything else on my car is torx. I probably have a 17mm allen. If not, I'm sure there's one at work. I guess it's a good thing I didn't make it to Sears yet.

I guess I'll drop by and get that hand pump. I still have to get 8 oz of gear lube out before I put in the posi lube. The hand pump might work better for me than the turkey baster.

There are lots of good ideas here. If I don't see the hand pump, I'll grab the turkey baster and go over the wheel.

Incidentally, I always wave. Even at C5s (though they never wave back ).

 

[Hib Halverson]

If this car "howls" when going around tighter turns at slow speed, as is suggested earlier in this thread, that is usually a symptom of a problematic limited slip differential.

Considering the car has 40,000+ miles on it, I'd change all the axle lubricant first, then add a friction modifier (or "additive" as some term it) in an attempt to quiet the noise.

However, since the car went for years and many thousands of miles before the limited slip began making noise, understand that friction modifiers can only address limited slip noise to a limited extent and they do it by degrading limited slip function, ie: the friction between the limited slip clutch plates is "modified" to be less.

If you change the lubricant, then and add one bottle of friction modifier and find the noise is still present to the degree it was before; there are no pour-in solutions.

You need to overhaul the rear axle because the limited slip is faulty.

 

[Whitehorse]

Thanks Hib. My manual says it's the posi. The symptoms say it's the posi. I'm just hoping that all it needed was new gear oil and some additive. If that doesn't do it, I've already found a rebuild for $350. I just have to find some local expert to do the work for me. I can't justify all these special tools just to do this job once (and possibly screw it up anyway). :bash

 

[Whitehorse]

Thanks Hib. My manual says it's the posi. The symptoms say it's the posi. I'm just hoping that all it needed was new gear oil and some additive. If that doesn't do it, I've already found a rebuild for $350. I just have to find some local expert to do the work for me. I can't justify all these special tools just to do this job once (and possibly screw it up anyway). :bash

Well it was the posi making the noise. 1 container of additive and she shut right up. It was howling all the time (when I turned) regardless of temperature. After the additive I haven't heard it again.

I just wanted to let folks know what the final result on this item was. Thanks to all for your help.

 

[John Robinson]

Thanks for Update

Thanks for the follow up on your thread. Now we know what solved your problem. What the heck some of us just feel good when we help others out and we know it.

 

[Whitehorse]

Yep, I thought it was important to let people know what fixed the problem so they'll take the advice of the others and try this first. $10 vs. $1500 sure makes a difference.

And then there's that added bonus of watching someone's head swell.

Cheers.

 

[Toms007]

Whitehorse, somehow I missed this thread until today.... I am glad that you figured it out, after reading your first post, I immediately thought "Posi additive". Always good to hear from another Kansan.

 

[Whitehorse]

Thanks Toms01. It was my first thought too and then I was told I was just plain wrong. That's when I looked up howling in my service manuals and it said the posi unit. DUH! Well the problem WAS the posi unit. I thought I was going to have to replace it but the problem was it needed the additive.

It started howling before I had the diff lube changed so that made it even easier to suspect more.

I've got 45K miles on this thing and the serpentine belt is dried and cracked so that is my next project. I'm also thinking about replacing the water pump while I'm in there. Anybody know a reason I shouldn't? I heard they go religiously at 50K. I may as well save my optispark and kill 2 birds with one stone.

Anyway, thanks again all.

 

[Toms007]

I'd say if you're that far, I'd go ahead and do it. When I had my 94 I had a small oil leak from the front of the engine. So I pulled the WP and opti to change out the three seals on the front cover. I had decided that if I had them off already I may a well replace them. Some people thought I was crazy, but I couldn't see any reason not to. I replaced the belt at the same time.

 

[navy2kcoupe]

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

Junk figured out L-O-N-G ago how to work "smarter and NOT harder"!
Glad the problem is solved .
Andy

 

[raidoman]

Howling Diff

I had the smae thing at about 45k in my 87. Used the turkey baster to remove old lube, added new and GM spec posi additive. Went to a parking lot nad did about 20 minutes of hard turning and the howl went away just like the dealer said it would. That was 7 - 8 years ago, now with 71k, howl has never returned.

 

[Oldskool153]

Just my 2 cents but why dont you take it to a vette specialist and have them tell you wat the prob is, even if it costs u $100 its cheaper than replacing a rear if you dont have to. Thats what I would do anyway

 

[Sunstroked]

Oldschool, he figured it out with the advice given him here. When he had the rear differential fluid changed, the shop who did it, did not add the limited slip additive required in posi trac units. After he added the correct amount his problem went away. That was much less than $100.

 

[Oldskool153]

lol yea I just noticed that he fixxed the prob, i appoligize for skipping ahead and not reading all the replys when i wrote my 2cents