Easier way to change transfer case fluid?

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aantalis
Posts: 47
Joined: Tue Aug 13, 2019 6:26 am

Easier way to change transfer case fluid?

Post by aantalis »

OK I’ve read the TSM about changing the transfer case fluid. Says I have to take out the filling and drain plugs from the transfer case and reduction unit and then loosen the reduction unit attaching bolts until you can pull the housing back to let it drain.

I’ve been having some stick-slip occurring on turns and I think the first step is to change the fluid. I plan on doing a torque bias test while I’m under there as it seems simple enough. 1979 Cherokee with 70,000 miles. It’s possible it still has the original fluid, I didn’t see any wrench marks on any of the drain plugs. The Area is clean and dry except for grease from the U joints.

Two questions. I’ve never done anything like this under a Truck before or on a bench. But it seems fairly straightforward. Is it difficult to pull the reduction unit away from the transfer case?

Second question
Is there a way to use a vacuum to remove the fluid through the drain plugs so that I don’t have to separate the unit from the transfer case. Or can I at least get 90% of the fluid up to see if it improves the condition?
Daily Driver for 24 yrs: 89 Grand Wag
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Tripwire
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Joined: Sat Dec 31, 2011 3:43 pm
Location: Washington state

Re: Easier way to change transfer case fluid?

Post by Tripwire »

loosen the bottom bolt let it drain, replace the plug, remove the fill bolt, a suction gun is very useful doing this.....be SURE to use the recommended fluid, since your down there dirty and oily, good time for a complete lube job

steve
FSJ.ORG JOIN DATE JULY 2000

Tripwire. 86 Grand. Howell fuel Injected 360. MSD Ignition + Dizzy. 727/228 BJ's 2" Lift and 31's

88 Wrangler Howell TBI and MSD - Borla Headers w/ Cat-back + winch and 31's AND a M416 trailer

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letank
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Re: Easier way to change transfer case fluid?

Post by letank »

First, remove the fill bolt, so you can be sure to be able to refill!
Being a shortcut guy, drain and inspect the type of fluid that drained... stinky like the QT fluid , this is good, then refill... but if it is red like ATF... then draining the reduction unit would be recommended... otherwise refill with QT fluid
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

will e
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Re: Easier way to change transfer case fluid?

Post by will e »

I am excited for you to tackle this maintenance effort. Many of these tasks seem a bit daunting at first, heck I have been wrenching on my own rigs for 50 years and still get apprehensive doing some stuff.

I found a transfer pump is one of the easiest ways to get the fluid back in.

This cheap one from Harbor freight works great.

https://www.harborfreight.com/multi-use ... 63144.html
81 Waggy 'WILL E' Retired
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letank
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Re: Easier way to change transfer case fluid?

Post by letank »

Good point on the transfer pump.... you can also convert a dove or dishwashing soap dispenser top, you need to find the right thread to the oil bottle, connect a hose after a little surgery on the cap, this set up is very nice to top off the transfer case for some of us who have leaky TC... you only need to squeeze the oil bottle... I'll try to locate mine and throw a pict

have a good 12" tubing to raise the bottle high above the refill
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Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

mattv
Posts: 35
Joined: Mon Nov 09, 2015 5:01 pm

Re: Easier way to change transfer case fluid?

Post by mattv »

I wonder if a mityvac would work for that
Provided you finangle the proper fittings
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devildog80
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Re: Easier way to change transfer case fluid?

Post by devildog80 »

If you can get the tube through the cap and down to the bottom of the bottle, you just squeeze the bottle and fluid would be pushed up through the tube.

If attached on the top, then you need to invert the bottle, to keep fluid going into the tube.
'81 CJ5 Base, 258 I6, MC2100, T176 4 spd, 300 TC, D30 Front NT, 3.31, 2-Piece AMC 20 rear NT, 3.31, 4" high arc spring lift
'84 Grand Wagoneer, 401 V8 (.030 over), MC2150 HA Comp, 727 auto, Selec-trac NP229, AMC 20 REAR - D44 FRONT - WT 3.31, 4" high arc spring lift
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