Differential Fluid Change Question (About RTV)

TJim

TJim

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Hey guys!

HELP!

Tomorrow I am going to do my first differential fluid change. I am going to change the fluids in both my Dana 30, and Dana 35.

I have the Mopar RTV. (https://www.amazon.com/dp/B008H2PL9S/?tag=wranglerorg-20)

I am going to apply the RTV in the cover, and slightly tighten the bolts. Wait a little bit, then fully tighten the bolts (with a torque wrench). Lastly, I am going to wait until the RTV is cured, so I can fill with the differential fluid.

My questions are:
1) How long should I wait between the first stage of tightening the bolts, and the final torque specs?
2) How long should I wait for the RTV to be cured. before filling with the differential fluid?

Thanks :)
 
Mopar RTV is applied to differential covers the same way that almost all other RTV products are applied.

The instructions on the tube should tell you to use a 1/4" bead, tighten finger tight until some RTV squeezes out the sides of the differential cover a bit, wait one hour, then tighten. [Do not overtighten, 1/4 to 1/2 turn is generally enough!]

The instructions should also tell you to let the RTV fully cure for 24 hours before filling with gear oil.

However, most technicians I know only wait 15-20 minutes before tightening the cover and an hour or two at the most before refilling. They have customers waiting for their cars and don't have the luxury of time to wait one hour before tightening or overnight before filling.

Many technicians I know are now using Permatex "The Right Stuff" rather than conventional RTV because there is zero cure time.

This DIY video should provide all the information you need:

 
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Thanks Guys!

My plan is to apply RTV -> finger tight it -> wait 1 hour -> use my torque wrench -> wait 2-3 hours -> fill.

I dont have the luxury to wait 24 hours.

Wish me luck! I hope I will have no leaks! haha :LOL:
 
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Zorba said:
Ok, somebody tell me why there just isn't a simple drain plug?
Click to expand...
Some people say they like to be able to see the condition of the internals.
Which has some merit, but who looks inside their engine when they change the oil? And the people that do inspect their diffs, how many times do they see anything worth noting?
Maybe take a look once in a while, but every time is unnecessary.
 
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Zorba said:
Ok, somebody tell me why there just isn't a simple drain plug?
Click to expand...

No idea.

If I want to look at the gears I'll do that. If I just want to change oil I use one of those gear oil pumps and suck the used oil out through the fill port. Fill it up with new and done.
 
Do not wait. Just put a bead on and torque it to spec. Leaks are primarily caused by waiting. You want metal to metal with the RTV just filling the gaps.

I talked to two of the most popular diff shops in Los Angeles years ago and both told me the exact same thing. RTV, install, torque, fill, no BS required. They even gave me some of the cheap RTV tubes most kits come with. They advised go with the cheapest stuff you can find, it doesn't matter.

Expensive gaskets work for some people and leak for others. Not something I want to test out.
 
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apply rtv, close, leave for a few min and refill.... this is literally a shampoo bottle directions level of complexity, you guys are making rocket science out of nothing.
 
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