I'm planning to fix my leaks except for seep on pinion seal my truck has plenty of oil leaks. I wouldn't get to this until end of this year beginning of next because of money. I'm just trying to plan now so I can do this sooner. Tired of checking fluid consistently once a week to make sure trans and engine has oil.

It leaks from:
Transmission front
Transmission shift shaft
Rear main
Oil pan

My plan so far for engine leaks:
Pull transmission
Pull oil pan, pickup tube and replace pickup tube gasket and oil pan gasket, while trans is out so I don't need to raise engine.
Replace rear main, curious as to what that entails? For a 302 it is a one piece by the research I have done (correct me if im wrong). Is there any special way to replace? Or just pop out and pop in?

My plan for the transmission:
Suck fluid out, pull trans (same time as above just listing again), remove pan and replace filter again, shift seal, reinstall pan with new gasket.
Replace front transmission seal, same thing there wondering what that entails? Just unbolt the torque converter remove, pop seal out pop new seal in?
For removing transmission, I would unbolt flex plate while connected to engine, support the weight of the engine with tie down straps from above somehow, unbolt transmission crossmember, unbolt the transmission from engine and remove?
And I can avoid pulling intake or worrying about screwing up wiring harness and hoses from major engine movement by raising.
Would I also replace driveshaft seal again since I have to remove the driveshaft and the rubbers got 1,000 miles to harden. I replaced it in march.
Would I fill torque converter before install since id drain it? Or would the pump in trans fill it?

The main problem im having parts wise:
What is the shift shaft seal called technically? For an AOD I see there is a shift shaft seal, and a manual shaft seal. Which one is for the linkage for the shifting linkage above the pan?
What seal is for the front of the transmission that's leaking? Is that an input shaft seal?

Another question is I am a high schooler, and will have to drive my moms car while this is taken apart so I would need to plan out how long id be doing that so she can make sure my dad doesn't need his truck. How long would this be down for assuming parts are gonna break removing stuff? What should I expect with my inexperience with this big of a job? I've done my timing chain so I have the skill to figure it out, just not skills specific to transmission removal. What problems should I expect? If I set a weekend aside for this job will I get it done? Maybe a week on a break? I have a Grandpa that has done this stuff before that can help guide me with the major stuff reinstalling the seals so I don't make mistakes and have to tear it apart again (at least that's what it should be that's never how it goes ). My dad knows enough to help me tear it apart. So ill have assistance and I've got a floor jack to put the transmission weight on to remove and install I can get some plywood to even out the weight. Anything else im missing?
I also used that Permatex gasket sealer on my diff cover for the paper gasket. Its a thin layer and it spreads on. It won't come off on anything into the oil pickup tube can I use that on the rubber/cork seals on trans pan and the oil pan? I would use normal RTV on the outer parts of the seals like the output shaft and input shaft style.
I assume parts will be about $400? Assume $500 for if something breaks? Maybe more if there's anything to replace that I haven't mentioned doing so in parts list below?
The parts list I got going:
6qts oil
oil filter
10qts transmission fluid since ill probably drain torque converter it took 4qts and 1 liter just removing pan.
Trans pan gasket and filter
Rear main seal
Oil pan gasket
Oil pump gasket for pickup tube
Engine oil drain plug
Transmission pan (https://www.summitracing.com/parts/s...D_BwE#overview) Is this good?
Dorman oil pan (will that be bad quality?)
Transmission rear output shaft seal

What parts Im not sure on links would be helpful different things pop up for one name for me:
Front transmission seal for leak coming from front between trans and engine
Transmission seal for the shift linkage above trans pan.
Thanks
Sorry this is so long but I want to make sure everything right. I don't got the money to be buying more stuff if I forget something or screw up.

 

You'll get a better deal on that sane trans pan on ebay IMO
Dorman pan is fine
Use no RTV on the seals or where the seal fits in the housing
If you have a gouged housing use aviation form a gasket or indian head gasket shellac on the seals painted surface
The shift shaft seal will make a man out of you, stamp your man card at least

 

Dang man, I teach 20-year-olds at a community college auto tech program and you're way ahead of where most of them are when they graduate.

Just looked up "shift shaft seal" and "manual shaft seal" for a 96 5.0 A/T, it's the same part. Look at the specs and you'll see all the dimensions are the same. Didn't find any info on the input shaft seal, looks like most parts houses call it a "torque converter seal"

My only nit to pick is, don't use any sealant on the O/D of the shaft seals. Install them exactly as they come out of the box. Some of them have a rubberized coating on the O/D, some of them have a plain ground finish, leave it up to the seal designer to pick the right surface finish.

ANY flavor of Permatex RTV sealant is OK for tacking the gaskets to the oil pans. The important part, as you seem to have figured out, is to not use too much. A 1/16" bead is sufficient. You might also want to try a product designed specifically for your purpose like "high tack gasket sealant". I've even used 3M spray-on trim adhesive. Doesn't really matter what it is as long as YOU find it easy to apply it neatly and cleanly without any gobs that will fall off after assembly. Also, FWIW, some oil pan gaskets come with little plastic assembly pegs so you won't need any kind of goo at all. And the trans pan has a metal core, so it will be no trouble at all to install without something to hold it up.

Dorman oil pans I've used have all been great. It's a pretty hard part to screw up, all it has to do in hold oil. What's wrong with the old one?

Yeah, your plan to remove trans is spot-on. Out is easy, getting it back in is the harder part.

You can probably skip the ATF filter and save $40. For many Ford auto transmissions (dunno if yours is one of them, look it up) the FSM says not to replace it unless it's known to be clogged or there's a line pressure problem. I've saved considerable time and expense leaving them the heck alone if they're still clean.

If it was my truck I'd spend the $4 or so to get a Plastigage and check the main clearance while the oil pan is off.

 

I won’t use it on the housing seals then, I was just gonna use the Permatex high tack gasket sealant on the pans. It’s designed to spread on instead of a bead so it doesn’t compress a lot and won’t fall off in the pans. I’ll just get a trans gasket then, I just replaced the filter and it’s only got 1k on it. Nothing wrong with the old oil pan. And for the trans it’ll have a drain plug. I just figure from over the years, it’s gonna be bent where the bolts are like my trans pan and I figured it’d be better to start with a fresh surface where I can so there’s minimal chance of leaks since it’s a lot of work to get to these seals. I’ll look at a plastigage.

 

I think the biggest factor im unsure of right now is supporting the back weight of the engine while the transmission is out if I want to remove the oil pan. How would I do that since I can't wrap a tie down under the engine? The only thing I have to hold the weight is tie downs.

 

Sooooooooooo many questions! Hey, we all start somewhere pal.

Starter out, find a local electrical joint to freshen up that starter IF you have that gear reduction one from later trucks. If not, may as well reuse old or find good used gear reduction. To jack the engine high enough to pull oil pan, pull the upper intake plenum...I have that bracket if you wanna bum it. I need to know quick as going out of town for a month, PM me. May as well have fresh injectors on hand, grab some from a 10th Gen as same dimensionally and flow but four pintle. Flow rates are wild on a 20 year old truck...a near 40? I bet worse.

Never used Dorman oil pan. Definitely use the updated Felpro gasket that is one piece, same with valve covers since access is easy. Agreed on checking rod bearings at least while apart. Consider a fresh Melling oil pump since in there.

Xylene is a boss cleaner and does not evaporate as fast as gasoline.

Since trans out, pop in a mild Transgo https://transgo.com/product-details/sk-aod/ this will keep it alive longer and STAY OUT OF OVERDRIVE IN TOWN. 4-3 and 4-2 downshifts hammer on the forward clutch pack. If you want slightly firmer shifts, get the HP kit and it also comes with better pump rings. Just buy a full paper and rubber kit from a joint like Transtar, it has all seals. I am sadistic and enjoy building transmissions. Do the pump bushing as that likes to leak too. Consider u-joints since driveshaft off. A 4R70W trans pan does NOT fit the AOD, tried it. I guess you could maybe redrill a hole, one was off. Never tried, sent it back and picked up Trick Flow's cast alu pan. Fits great, my truck has the B&M pan. Dicked with this in May on my pal's '89 where I did his Transgo HP kit. Get a good cooler since down, I like the B&M 70264

All I have for now!

 

Starters fresh just installed it a year ago. Would I still need to raise engine since trans would be out? Shouldn’t it just slide backwards if the pickup tube is taken off? I shouldn’t need the upper intake plenum anytime soon, I have to get the money to buy these parts. Probably won’t happen for a few months at least. I’ll look into those trans kits. Thanks for the info.

 

Wrap an old seat belt around the intake runners and lift straight up. Or lift eyes if your motor still has them. After it's up shove blocks of plywood in between the motor mounts and the frame and let it come to rest on those, but with some tension still on the seat belt to hold it up if the blocks shift. If you don't have a hoist, jack it up by the oil pan with the trans still in, put blocks under the motor mounts, then remove the jack, trans, and oil pan. If all the pipes and stuff are still bolted to the engine it won't rock back and forth, it can only move up and down with the hoist. If it makes you feel better take the trans out and rock the engine back and forth by hand, you'll see what I mean. It's pretty hard to move it even a little bit.

 

Upper is six bolts to pull is why I suggest it, easy!

 

So I was thinking about it more, how much more work would it to be to pull the engine with the transmission? I feel like that would be a better option to clean things up. But if I did that I’d need to redo the AC system to because i can hear the compressor when it’s running 😬. I looked on prodemand and it said it’s about a 6.5 hour job for a professional to pull the engine so I figure that’d be 7 if they take the transmission with it. So for me it’s probably gonna take a weekend to pull, a few weeks to clean things up when it’s out since this things the definition of disgusting under the hood with all the previous leaks. And 1/2 to a full week to reinstall. This would be the first time I pull an engine whenever I’m able to follow through with it. Especially since I’ve been procrastinating it. I could get a cherry picker and the bracket for the intake plenum to pull it. I figure it’d be about $1100 to redo the AC myself minus the cost for a shop to charge and for new seals? Maybe $2000 total if I can get around to paying someone to rebuild the transmission? I think seals were only $100-200 for them all. And then the AC was around $800 and I figure a trans rebuild on an AOD being simple is like $800?

 

The dorman replacement 3800 oil pans for the 3.8l v6 series 2 engines from gm are bad , the steel ones that is. They originally are laminated polymer between two stamps of steel and the perimeter doesnt use spreaders and uses 8mm bolts and basically the pans were made with such bad tolerances that they just leak a lot. So the aftermarket ones do to

Also their 4t65e pan is badly machined

 

If you replaced all AC bits, figure maybe $400...since you are an '88, at least go to '89+ stuff for easier to attain parts and better compressor. 100% at least do a small tube condenser or do like I did on my '92 and my pal's '89 and do a parallel flow....only issue is you need to change up the liquid line slightly. E A S Y. These are beyond cheap to repair and if the AOD is dying, find a 92-93 core and build it yourself while the truck still runs. AOD is comically simple to reman, plus the late ones have all the updates available.

Where are all the oil leaks? I always start at the top and work my way down.

 

I can look for a core, it’s not dying I just figured since I’ve been checking the fluid incorrectly it’s gonna have some damage from being overfilled and I don’t know how many miles are on it. It’s kinda just a while I’m there thing. It’s the front of the engine oil pan, the back, possibly rear main, front of the transmission, and shift shaft seal.

 

your rear end, a 8.8 has 4.10 limited slip in it?
i just read your signature.. are you sure about that

 

It’s non limited slip. I need to look at my signature on a device that shows that and correct it if it needs to be corrected. It’s supposed to have 3.55 gears from the factory but the PO changed them out apparently.