Ok so I've recently replaced the cover seal on the rear diff on my 02 ranger XLT, 5-speed.

I took off the cover and cleaned both the diff case and cover, quite extensively, with brake cleaner. I applied a 1/8" bead of Permatex "Right Stuff" to the diff case surface and the cover surface, sandwiching a $5.00 Advance Auto gasket in between. That "Right Stuff is supposed to set in less than a minute so without hesitating, I carefully lined up the holes in the cover with the bolt holes in the diff case and tightened the bolts to 8-10 ft.-Lbs.

I waited a half hour, then dumped a bottle of friction modifier plus 3.5 quarts of gear oil (damn that seemed like a lot of oil for that tiny diff case) into the diff case. **Note: That filler plug was slightly difficult to find.

I drove around for about 150 miles, only to notice that the seal is STILL leaking! WTF did I do wrong???

 

you didnt turn around 3 times and pat your shoulders while spitting before you cranked your truck up.

 

redo it, then just let it sit overnight and fill it up in the morning

I always use RTV high temp silicon gasket and don't have any problems

 

If I had wanted a sarcastic answer, I'd have posted a question about Ford trucks on a Geo Metro forum.....

 

chill out. Didnt mean to make you upset lol. I wanted to post here so i could be reminded when an answer popped up so i would know what to do when the problem arised with me.

 

use gray RTV, there is no use in the world for black RTV except for writing your name on the side of your hoist when you are bored

 

lol

 

I use high temp orange. There is no need for an additional gasket in there. My guess is that's why it is leaking. Just squirt the orange high temp rtv, let it sit a few minutes, put the cover on and tighten the bolts by hand, let it sit again then tighten the bolts.

 

X2. i did that with black, and have yet to have a problem.

 

I used the RTV high temp orange. Worked great. Wouldnt use anything else. Used the stuff on tractors at work and they have held up fine from the abuse.

 

There is no need to use RTV with a cut gasket. Use one or the other. It is fine to use gasket sealer on a cut gasket (as intended), but not RTV.

I use Permatex Ultra Black, which is intended for this kind of use. Put a bead on the cover, put the cover on the diff, and let it sit for about an hour before filling. I have never had any leaks with this method. As an alternative, you can get a Felpro cut gasket at most parts stores, and spray some sealant on it (comes in a spray can or tube, it's usually next to the RTV).

 

3.5 qts may have seemed like a lot for the "tiny diff case" because its actually 3.5 qts for the whole rear axle.

all you can do is try again.

 

Well, there was definitely an RTV gasket on there in the first place, since I had to scrape it off.

I absolutely HATE working with RTV because I've never been able to make a seal with it. Maybe I'm not letting it sit for long enough. That it itself, however, arises another problem. I never ever have enough time to what needs to be done for a proper job. Racing against the clock sucks.

So, basically, I've wasted 8 bucks on a tube of RTV that I cannot use.

 

lol
I don't know, I let mine sit for an hour normally. But the guy who re-geared my f150 let it sit for 3-4 minutes only and it hasn't leaked a drop.

 

Make sure things are clean, clean, clean.
Double check the mating surfaces are smooth no marks across the surface and double check for cracks.
Then take alcohol and clean off the sealing area.
Apply the silicon OR the gasket sprayed with Hy-Tach Gasket Treatment but NOT BOTH !
Most people use just the silicone sealer by itself, I prefer (from the Harley Days) to use Hy-Tach Spray on Gasket Sealer w/ just the gasket.

Oh ya the biggy - Sometimes the mounting holes start to taper inward and will not seal so tap the area flat.
This applies if using a Stamped Steel cover as most of us have, made sure the sealing surface is flat. If not take a small hammer and tap (lightly) the surface using a good solid backing to tap against. Tap around the holes first inside out then go around the outside of the sealing surface and tap it flat; might be a good idea no matter what.

Luck.

p.s. as suggested let the sealers set, per the package instructions, no matter which one you use.

 

Yes, but there wasn't a cut gasket. RTV will work fine if you let it cure properly and if it is being used by itself. If it comes into contact with oil before being allowed to cure, or if there is a paper gasket sandwiched between it, you are not likely to get a good seal. RTV and cut gaskets are two different types that are not meant to be used together.

It sounds like having enough time is the main problem. If you use RTV, you have to let it set up or you will be doing the job again.

 

Start the gasket at night, just over hand-tighten it, then tighten it down good in the morning before you fill it up, then go to work.

 

Double check the Mounting surface of the Cover…

 

I used the permatex orange with copper stuff in it. Havent had any problems

 

Yeah... I went to Auto Zone today and tried to order another cut gasket. All they had was the diff cover itself, along with a magnet and a cut gasket, all as part of a kit for $20. I went ahead and ordered it, seeing as how my current diff cover is rusted to hell.

So, basically, just use the cut gasket with NO rtv, or just throw the cut gasket out and use rtv ONLY??

 

got me one of these they are reusable

LubeLocker - Differential Gaskets

 

Lube Locker Gaskets look good and I bought one for the D-60 in the Jeep but if you don’t have a gasket and you need one or want to use one use a Bud Box.
Take a 30 pak and cut a gasket out of the side of it.
Spray on some Hy-Tack, twice or even three times letting it set between coats and you have a great gasket.
The material of the Bud 30-Pak is dense enough to hold its shape under pressure.

I have used the Bud Box Gasket and they work as well if not better than most others.
Main thing you need is to cut it out and make sure to spray it with Hy-Tack.

luck.

 

I don't know why you are bothering with other gaskets to be honest. Just use RTV by itself, it IS the gasket.

 

You don't tell us what year your truck is, but all the newer Rangers have been using a plastic composite cover instead of metal, and these covers don't use a gasket, only RTV.
When working with RTV, several things are necessary for success.
Cleanliness is #1. If any oily film exists, the RTV won't be able to adhere to the sealing surfaces, so clean them perfectly with elec. contact cleaner, alcohol, or some such solvent. No oil allowed! Do whatever necessary to maintain the cleanliness.
Requirement #2 is that the surfaces must be mated before the RTV skins over. Once it starts to skin, it won't seal. Do not "wait a bit" before mating the surfaces or you'll get a leak.
Older RTV will skin faster than new fresh RTV. For best results, only use RTV labeled as "Gasket Maker" or something similar. Other types aren't designed for automotive fluids and sealing purposes.

 

You can let it "sit a bit" and I've done it a handful of times, it is also what I have seen several shops do. I'm not saying to let it sit on there for an hour, but squirt it on and let it sit for a "few minutes". Once you put the cover on and tighten the bolts with your fingers it will squeeze out and seal up anyway.

But yes it needs to be clean. Auto parts stores sell gasket remover in a spray can, that is what I use. Spray it on, let it sit, scrape off with a plastic scraper tool. After I get it wiped down clean I use a little alcohol as well to clean it.