Water contaminatin in the rear end

mimoss · Post by **mimoss** » Wed Dec 19, 2007 7:22 am

OK, so I have had water contaminate my crew 2 times in the rear differential and axle ect... The 2nd repair was made six weeks ago and my truck is now acting up again. The rear wheels are locking up when I turn; this is the same thing that happened the last time water got into the diff, but it should have been fixed. I relocated the diff vent hose. After reading my invoice from the last repair I noticed that the mechanic stated that they put in Aimsoil synthetic and a bottle of POSI Additive. Could this POSI Additive be what is making my rear wheels be locking up in the turns?? I do have the G80 Locker and I thought that the only diff that needed the extra additive was the limited slip differentials. So my truck was great for 5.5 weeks after these last repairs were done, but now its locking up the rear wheels again. So I'm wondering if it was the extra POSI Additive that is now causing problems. Any suggestions would be great!! Thanks!

killian96ss · Post by **killian96ss** » Wed Dec 19, 2007 9:12 am

The G80 Eaton Gov-Loc does not require posi additive and it should not be used with this type of locker.

The factory service manuals and even the owners manual specifically say NOT to use limited slip additive with the G80.

I don't know if it will cause the wheels to lock up or not, but you should go back to that shop and have them replace the rear end fluid "free of charge" since they made a mistake adding that fluid.

I would also try a different brand of gear oil like Mobil 1, Redline, or Royal Purple.

I have had good results with Redline 75W-90NS (NS = no limited slip additive) with the G80.

Steve

kwalsh · Post by **kwalsh** » Wed Dec 19, 2007 10:01 am

When you had the rear serviced was the diff cover replaced or inspected?

My OEM cover lasted about 3 years. I had to replace it because it was rusted through and allowed moisture/water to enter the rear. It was very obvious when I serviced it.

For good measure I applied some RTV silicone sealant around the new gasket.

Regards,
Kevin

Post by **HenryJ** » Wed Dec 19, 2007 10:10 am

The water may already have done the damage. Hard to blame the friction modifier or the Asmsoil lube alone, but those two are on the list for for those who have had problems.

They should pay for a drain and refill, but if they find a bad G80, that will be up to you to bear the cost of replacement.

Sorry you didn't find the problem sooner , and save the rear differential.

mimoss · Post by **mimoss** » Wed Dec 19, 2007 10:21 am

kwalsh wrote:When you had the rear serviced was the diff cover replaced or inspected?

My OEM cover lasted about 3 years. I had to replace it because it was rusted through and allowed moisture/water to enter the rear. It was very obvious when I serviced it.

For good measure I applied some RTV silicone sealant around the new gasket.

Regards,
Kevin

The last repair did not included a new cover. It is rusty and still the stock cover from 2001. So it may very well be time for a new cover. Thanks for the info!

mimoss · Post by **mimoss** » Wed Dec 19, 2007 10:33 am

killian96ss wrote:The G80 Eaton Gov-Loc does not require posi additive and it should not be used with this type of locker.

The factory service manuals and even the owners manual specifically say NOT to use limited slip additive with the G80.

I don't know if it will cause the wheels to lock up or not, but you should go back to that shop and have them replace the rear end fluid "free of charge" since they made a mistake adding that fluid.

I would also try a different brand of gear oil like Mobil 1, Redline, or Royal Purple.

I have had good results with Redline 75W-90NS (NS = no limited slip additive) with the G80.

Steve

I did explain to the mechanic who last did the repairs and put in the posi additive in that it did not need to be added and he became very defensive and stated that every posi differential needs the additive. I then calmly explained that even in my truck manual it states that you do not need to add any additive. He got pretty upset by what I was telling him and I wasn't even sure I would want him back working on my truck. I guess if you want something done right you just have to do it yourself. It's just upsetting that you pay so called experts money to do a job correctly and you end up having to do the research youself anyway to make sure that the job was/is done correctly.

killian96ss · Post by **killian96ss** » Wed Dec 19, 2007 10:47 am

mimoss wrote:I guess if you want something done right you just have to do it yourself.

This is why I do all my own work.

Steve

LUVMY02CREW · Post by **LUVMY02CREW** » Wed Dec 19, 2007 7:04 pm

killian96ss wrote:
mimoss wrote:I guess if you want something done right you just have to do it yourself.
This is why I do all my own work.

This fact has slowly but surely been getting through my thick skull. Just gotta start making more time so I can save a few bucks.

This forum has made me put way too many things on my "really need to check this out" list.

I guess the rear diff and fluid are now on it too....

mimoss · Post by **mimoss** » Thu Dec 20, 2007 8:44 am

Ok so I opened the rear differential cover and found that the fluid looks to be in good shape (no water contamination) Just that it has the posi additive that it shouldn't. My rear cover looks like it is in pretty bad shape though so I will see if I can get a replacement for it. The outside is very rusty and the inside has fine pits everywhere where the gasket goes.

Do the gaskets for our differential dissolve at all because it looks like a gasket was not even used for my differential cover... There is only alot of the gasket sealer. The last repair was made only 6 weeks ago and less than 1000 miles. Hopefully after I get new lube in there without the posi additive my rear wheels will stop locking up around corners. [/img]

Post by **HenryJ** » Thu Dec 20, 2007 8:49 am

Check out the threads on diff covers. I like the support covers modded for lubrication.
How about a shot of the carrier.
Personally I would go back to the recommended fluid. I don't want to get in to the whole synth vs GM lube thing again. That is covered in another thread. I would not add amsoil again, nor the additive.

mimoss · Post by **mimoss** » Thu Dec 20, 2007 9:35 am

HenryJ wrote:Check out the threads on diff covers. I like the support covers modded for lubrication.
How about a shot of the carrier.
Personally I would go back to the recommended fluid. I don't want to get in to the whole synth vs GM lube thing again. That is covered in another thread. I would not add amsoil again, nor the additive.

Yes, I would like a cover with a drain and fill plug. Here are some shots of the inside. Do you see anything out of the ordinary?? I'm a little out of my element with this stuff. Thanks!!

Post by **HenryJ** » Thu Dec 20, 2007 9:59 am

Clean it out as best you can. I have used aerosol brake cleaner, or electrical cleaner to wash things down in severe cases. Wipe it out and let it dry out a little before closing things up. a little air blown around can help push out contaminants.
Make sure the fly weight is free. Jack it up and rotate one wheel. Make sure the spider gears turn freely and there is no binding or roughness.
If it all sounds good and feels good, then install the cover and fill with GM Vehicle care Axle Lubricant SAE 80W-90.

killian96ss · Post by **killian96ss** » Thu Dec 20, 2007 10:14 am

Looks normal to me.

I guess that shop is too cheap to use a gasket.

Even though it's not a requirement to use a gasket I have found that a gasket will help prevent future leaks, and you can cut open the passages for proper wheel bearing lubrication.

Redline 75W-90NS gear oil works great with the Eaton Gov-Loc.

I have used this same Redline fluid in 3 different Eaton Gov-Loc equipped vehicles with a combined mileage well over 150k and have nothing but good to say about this oil.

The Gov-Loc functions just as it should and the synthetic oil has far superior wear protection, heat protection, and longer drain intervals that regular "dino" gear oil.

Summit Racing, Trick Flow, LPW, T/A Performance, etc. all make nice aluminum rear end support covers if you want something that is a lot stronger than the factory cover that also has fill and drain holes.

Steve

Post by **HenryJ** » Thu Dec 20, 2007 10:19 am

Read this thread: Getting a chattering in turns from the rear end.
I disagree with the use of synthetics where clutches are involved, unless otherwise specified.

killian96ss · Post by **killian96ss** » Thu Dec 20, 2007 10:30 am

Here is some info on those aluminum support covers.

TA Performance, Summit and LPW 10 Bolt Rear End Covers

Don't let Brule scare you away from synthetic gear oil since there is nothing wrong with the stuff and it works perfectly fine with the Eaton Gov-Loc, not to mention the added benefits mentioned above.

Amsoil is the only fluid I have ever heard problems about.

Steve

mimoss · Post by **mimoss** » Thu Dec 20, 2007 11:21 am

So I just got back from 2 GM dealerships in town. I had to just get a regular stock cover. I called about 15 auto parts stores and no one had a rear diff cover in stock. I really want/need to get this done tonight. I asked the GM parts guy for the GM Axle lube part number SAE 80W-90 1052271 and he stated that that number was the old number and he looked up the new stuff for me. So I got Axle Lubricant SAE 80W-90 part number 89021671. I So I'm just hoping that this is the right gear oil because on the back of the can it says it is GL-4 and compatible limited slip modifiers. The one guy at the GM parts place was trying to talk me into putting in the friction modifier even after I told him that I have the G80 Locking rear end. Also, when I did get the oil, I asked for 2 Quarts and they gave me 2 23oz bottles so I politely asked him for a 3rd. I remember reading on this site that someone else had that problem. I'm glad I discovered it while I was still there.

Post by **HenryJ** » Thu Dec 20, 2007 11:25 am

Thank you for the updated part number!

I had been searching for that and could not find it. I will update the information with that part number.

Another diff cover option is to grab a cheap chrome cover for an Astro or Camaro.

mimoss · Post by **mimoss** » Thu Dec 20, 2007 11:27 am

HenryJ wrote:Thank you for the updated part number! I had been searching for that and could not find it. I will update the information with that part number.

Another diff cover option is to grab a cheap chrome cover for an Astro or Camaro.

Surprising the stock cover at the dealership was only 17 dollars. I'll be prepared in the future though and pre order a aftermarket cover.

Post by **HenryJ** » Thu Dec 20, 2007 11:37 am

That price is pretty reasonable. They must know that they have a problem. Many times I see prices low on parts they end up replacing in a good faith policy, or other special policy. I wonder if they are dealing with some "issues"?

mimoss · Post by **mimoss** » Thu Dec 20, 2007 3:10 pm

So I do have the differential cleaned out by using brake cleaner and compressed air. Also, the gasket and new cover are on. I did notice that my magnet on the original cover was gone though. I didn't notice until I got the new one out to put it on.

Also, in my oil pan after closer analysis I notice a lot of tiny what I believe are shredded magnet pieces. I ran a magnetic tool through the oil and it picked up a lot of the above mentioned pieces. So now should I still have to wait a couple of hours to put in more fluid, but now I'm wondering if I need to just put in cheap crap oil and then do the same differential fluid change in a few days. Or should I just put the good GM oil in it now and hopefully everything will be fine. I cleaned it out pretty good and I didn't see anything like that in the inside of the case. So this time my differential was not contaminated with water, but with tiny pieces of magnets. I'm just wondering when that magnet fell off?? I'm almost sure this is the reason why my wheels were locking up in the turns becuase of the newly contaminated gear lube.

Post by **HenryJ** » Thu Dec 20, 2007 3:16 pm

Nice. You don't own any ducks do you? If you do, keep them away from water. They will surely drown.
Magnetic debris would be very hard to clean out. Flush and blow is the best you can hope for.
Do your best to account for all the pieces and cleaned out as best you can. Put it back together and hope for the best. If it gives you problems in the future plan on doing this all again.

F9K9 · Post by **F9K9** » Thu Dec 20, 2007 4:22 pm

HenryJ wrote:Nice. You don't own any ducks do you? If you do, keep them away from water. They will surely drown..................

Hmmmmmmmm

Post by **HenryJ** » Thu Dec 20, 2007 4:40 pm

Better check your lineage. [Darthvader voice]"Luke, I am your father..."[/voice]

Luck like that just has to be genetic.

S-10CREWCAB.NET

Water contaminatin in the rear end

Water contaminatin in the rear end

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