Embarassing question

[78Suburban]

This is kinda humiliating to ask, but I am new to working on my own 4x4. It's time for me to do some basic maintance and I need some help. How do I cange the oil in my 203 t-case and how much do I put (I know its 10w30). How do I cange the oil in both diffs and what weight/brand should I use and how much? what type of ATF do I put in my turbo400 and again, how do I change (drain&fill) it and how much do I put? Is there some sort of transmission filter I need to change as well? My 350 takes 7 quarts of oil, right? what wieght would yall recommend for the Georgia summer heat?

I feel retarded for asking these basic questions, but I have always been lazy and broght my trucks to the shop for maintence, except for engine oil. I really dont want to shell out the money for someone else to do all of this. Any advise/instructions on how to do these maintence procedures would be Greatly appreciated.
Thanks

 

[thatK30guy]

Drain the 203 by removing one of the lower bolts on the very back part of the case where you see a round aluminum cover, about 8" in diameter and let the fluids flow out. The fill plug is on the back part right by that cover, too, to fill it back up.

The axles need to have the covers removed to get the oil out. Remove the bolts, drain, clean up the covers, install a new gasket and/or RTV sealant and bolt the covers back on. Fill the axles up with 80/90 oil.

The turbo 400 tranny needs to have the pan dropped to remove the fluid. Simply remove the bolts and let it drain. Clean the pan and install a new filter while you've got it off. Install the new supplied gasket and bolt everything back up. Fill it back up with Dexron/Mercon tranny fluid. Quart capacity depends on whether you have a shallow or deep pan.

 

[mrhoes]

I am not sure about what kind of oil for the 203 but the diffs take 90w just unbolt the cover let it drain put on a new gasket and fill them up until it leaks out of the fill plug. On the 400 drop the pan get a new gasket and filter and make sure you get the little o-ring out of the valve body where the new filter goes it comes with a new one, I think a 400 takes about 5 to 6 quarts when you just drop the pan. your 350 should take 5 to 6 quarts of oil

 

[SkulzNBonz]

For the 203, there should be a drain plug near the back (rear) at the bottom (but not ON the bottom). Open and drain. To refill, fill at the fill plug until oil starts coming out of the fill, that's full.
To drain and refill the diffs, you have to remove the diff covers to drain them. Replace gaskets or, if you wheel often, use RTV instaed of gaskets, because you will want to change the fluid pretty regularly. To refill, the front cover has a fill plug in it. For the rear, the fill plug is on the passenger side of the housing (differential). For fluid, if your diffs are open, 80-90 weight store brand gear oil is fine. If you have the dreaded Factory Posi (Gov Bomb) in the rear, use a good 80-90 that has the limited slip additive.
ATF is Dexcron-Mercon III. Brand is up to you. Drain is pulling the pan. There is a filter. Don't know on capacity. Auto store should be able to tell you.
I use 10W-30 weight engine oil year round in Oklahoma. Seven quarts sounds high, I want to say my 305 holds five.

For about $15, you can get a Hayne's/Chilton manual, and answer all these questions from there.

John

 

[Mad-Dog]

The 203 has a drain plug near the bottom and fill plug slightly higher (several inches higher), I'm thinking the 203 uses gear oil...maybe

place a drain pan under both diffs and remove all bolts in covers except for the top 2 or 3 then loosen these remaining bolts 1-2 revolutions and crack the covers open from the bottom and the fluid will drain out into the pan...
once it slows to a trickle remove the covers, scrape em clean and reinstall,
then fill both diffs with gear oil.

The tranny is drained the same way...place the drain pan towards the front of the tranny pan and let the front of the pan tilt down SLOWLY as ther will be a lot of smelly, burnt red fluid splashing out the pan as you lower it,
let her tilt as far as it will go then drop it, clean everything up nicely while changing the filter......now look at the bolt holes in the pan and use a small ball peen hammer to level the indentations around each hole caused by overtightening the pan, this ensure the gasket seals nicely and don't leave blood stains in mommas driveway.
Dexron II is the norm for GM trannys (not sure how much, but p/u a couple gallons for ships n giggles.
The engine will accept 5 quarts of "10W-30" and i would run Amsoil if ya love ur motor.
There are no retarded questions here my friend, just retarded answers..
please don't hesitate to ask us for advice as we are here to help you..

 

[78Suburban]

is ft/lbs of torque a major concern for the diffs? how do I know if I have factory limited slip or not? So I fill the t-case and diffs untill they flow over, right? How do I get the oil to the fill hole on the t-case? Any ballpark figures on how much oil the t-case takes, because my dad is in town and I might call his cell phone and get him to pick me up some oil for the t-case so I can change it today.

thanks for the advise

 

[gambit420s]

to fill transfer cases with oif or atf you can try using a screw-on nipple(like is on lucas bottles) and a piece of hose and just sitck the hose on the nibble and in the fill bung, turn the bottle upside down and squeeze. you can also poke a hole in the bottom of the bottle and use an airgun to pressurize the bottle, same principal just a little quicker. for diffs or anything that takes gear oil i bought a hand pump that fits gallon bottles, it has a fitting on the end that grabs the fill hole so it doesnt come out, makes it real easy to just pump it in till it spills out.
AFAIK
Diffs take 80W90 Gear oil (posi use a friction modifier in addition)
All HydraMatic transmissions use Dextron ATF (usually sold as dextron/mercon III)
Transfer Cases use 80W90 gear oil or ATF depending on model(i've never seen motor oil used in a t/c)
Manual transmisions use 80W90 gear oil, or ATF, but some cars (hondas that i know of) use motor oil.

 

[divorced]

how do I know if I have factory limited slip or not?

If it has only spider gears then it is "open". If you are not sure you can take a pic and post it up, or search online and find a pic that looks like what you have.

So I fill the t-case and diffs untill they flow over, right?

Yes

How do I get the oil to the fill hole on the t-case?

I use the cone shape spout that comes on top of the 80/90 weight bottles. You can screw it onto your 10W-30 oil bottle and put the tip in the hole and squeeze the oil out. You can also use a short piece of rubber hose as an extension if you need to.

Any ballpark figures on how much oil the t-case takes?

I think 2 quarts. Just buy some extra; you can always use it in your engine.

 

[Mad-Dog]

I use a length of clear tubing that fits inside the fill hole and stretch the other end over the nipple on the bottle.......then u can manuever the bottle to a place higher than the fill hole and squeeze away.

Just snug the all the bolts up using a 3/8" ratchet and u'll b fine...

when u pop the covers and look inside the diffs if ya see some type of friction discs and spring setup in the carrier then ya got some type of limp slip or locker unit....

 

[78Suburban]

http://www.off-road.com/chevy/f-faqs.html

this website says use 10w-30 motor oil for the t-case, are they correct?

 

[POWERMAD]

Yes the 203 takes engine oil.
It has an internal pump that won't push the lube if it is heavy gear oil.

 

[thatK30guy]

Too many replies and people repeating one another.

 

[Mad-Dog]

As far as i can tell it takes 10W-30 as stated....i am not a fan of the 203 as i ripped mine out and replaced it with a 205 and twin-stick shifter before i even drove the truck for the first time.

The 203 is a full-time case which turns the front axles all the time and is not the best choice if fuel mileage is a concern, i still have the manual hubs so i still have to get out and lock each hub after engaging the front axle
with the 205.

 

[78Suburban]

fuel economy isn't really a concern for me. I just hope it's not extremely weak/unreliable. it is a 203 if it says highloc, high, neurtral, low, lowloc.......................right? I wish I had the 205

 

[divorced]

fuel economy isn't really a concern for me. I just hope it's not extremely weak/unreliable. it is a 203 if it says highloc, high, neurtral, low, lowloc.......................right? I wish I had the 205

Yep, that's a 203. I hate them. I replaced 3 of them in one truck in one year. Never again will I try to run a 203.

 

[78Suburban]

thats not real encouraging. I wouldn't have been so egar to buy the truck if I had realized that the t-case was crap. At least the motor and tranny are top notch .

Well, I guess I need to swap in a 205, I don't even know where to start as far as finding one for a decent deal and how in the heck am I going to install the thing.

I mean, how bad to these 203's really suck, is it a sure thing that it will break as soon as I do any mild muddin?

 

[divorced]

You may be alright with it, and maybe I just had some bad luck? I would just run it until it breaks and worry about it then. A 205 swap would be dinero grande because the t-case and adapter aren't cheap and you will need different lengths driveshafts. The 203's that have gone out on me have all had chain problems from high miles. Your's may last you forever.

 

[Mad-Dog]

Don't be too quick to discount the 203......it's a OK unit for mild 4 wheelin.
The chain drive is the weak link and causes the most headaches,
a part-time kit is available but not recommended.

A 205 with the adapter is readily available in your local scrap yard for a few hundred dollas....then ya gotta get some goodies from Off Road Design
like their drive sleeve and twin-stick shifter....oooh lala....good stuff.

If ya got money to spend there are a couple of aftermarket T-cases out there that make fine replacements for the 203 such as the Atlas II unit,
over/under drive units....u name it, somebody makes it.
Here is 1 of hundreds..............

http://www.dimensionoffroad.com/products/advanceAdapters.html

This hobby gets real expensive....real fast, but it sure is fun.

Take care and good luck my friend

 

[ntsqd]

I wouldn't worry about the 203 until it becomes a problem. Just set a little aside for the day that may or may not ever come.

Know that they are a heavy pig though. The kind that takes two men and a boy to move. There are better options out there for what ever you plan to do with the truck. For now I'd go with what you have. Let how you actually use the truck determine if and what to replace it with.

FWIW, my '79 Sub gets used for expeditions and trips. The 203 in it was toast when I got the truck. I replaced it with a 208, with is not the strongest t/c out there, but has a lower low range ratio than the 205. It's also far lighter than a 205. The 208 would not be my choice for hard core wheeling or mud, but it's fine for my use.

Transfer Cases use 80W90 gear oil or ATF depending on model(i've never seen motor oil used in a t/c)

FYI Bronco Dana 20's are also spec'd for engine oil, straight 50 wt as I recall.