Any recommended "extra" work while the tranny is out?

[MMcc]

My transmission's skirt keeps getting shorter -- showing its last legs. 1997 Suburban, 202,000 mi
I was way out there on a BLM service road this weekend, shifted 3->2 downhill at ~40mph and...scary sounds (a moment of grinding followed by it sounding like it freewheeling? loud whirring). Shifted to neutral, slowed way down, and got her back into gear. A little later I tried to reverse and she told me that was also a bad idea! (terribly grinding). No CEL. Nursed the baby home.
Sounds like a failing sunshade based on #7 of Answer to any 4l60e Trouble post.

Slowly, this truck is growing up to be an overlander, so reliability is always nagging on my brain.
I'm inclined to order a remanufactured tranny w/ TC and swap it myself. Any online shops to stay away from?

What other work would you do while you're in there?
- Rear main seal.
- Flush the trans cooler (kooler klean).
- Tap-in a drain plug? (After this investment, I plan on regular fluid changes!)
- Inline trans fluid filter??
- Temperature sensor and gauge? (Off roading in Utah heat...)
- What else??

Cautionary tale FWIW - this happened about 1000 miles after putting 33" tires on the Burb. Tranny was weak before, and shifted hard 1-2. But still, it feels connected.

 

[TechNova]

drive shaft U joints and transfer case rebuild

 

[alpinecrick]

Aftermarket drain plugs for a trans pan sorta' kinda' work.

These have worked best for me.
Deep pan: https://www.cfrperformance.com/CHEVY_GM_700R4_4L60E_4L65E_STEEL_TRANSMISSION_PAN_p/hz-9712-pbk.htm

Standard pan: https://www.cfrperformance.com/CHEVY_GM_700R4_4L60E_4L65E_STEEL_TRANSMISSION_PAN_p/hz-7599-pbk.htm

These pans are steel, they're rugged, the drain plug doesn't seep. The bottom of the deep pan is slightly above the crossover exhaust pipe and provides plenty of clearance. When I pull the plug on my deep pans 6 to 6 1/2 quarts of fluid come out. With the factory external coolers in my 5.7's total capacity is around 16 quarts.

Ignore the recommended service interval.

I drain my pans every 6k to 10k, usually when I'm draining the engine oil. It's easy when I'm already under there. On a newly rebuilt trans, I drop the pan, clean the magnet(s) and change the filter within a thousand miles. After that every 25k to 30k between filter changes.

My trans builder says for transmissions designed more than 10 years ago he sees no advantage to synthetic ATF ( some may disagree). I buy Walmart SuperTech and Valvoline synthetic (at Walmart), and use them interchangeably. It's more important to keep the fluid BRIGHT RED, not red, not dark red, not brown, not black, rather than use Royal Fuchsia ATF made by Bavarian elves on Mars, and then try to go a million miles between fluid changes.

Stay away from boy racer parts like 8 clutch packs and such. They work well for the short term at the track, not so much for long term reliability.

A Beast style sunshell is a must.

Buy the best torque convertor you can afford. But not a TQ for a hot rod--especially if you're cruising the BLM ground out in the desert 4 wheeling.

 

[thinger2]

Yep to all of the above. Dont let them re use the torque converter.
And pull the flex plate off and check it for cracks and runout.
If you decide to replace anything, be very carefull about bolt lengths and shoulders and grip range.
Dont buy bolts that bottom out before they capture and torque

 

[stutaeng]

When I pulled my 4L60e the "extra" work for me was to swap to a 4L80e, LOL.

With big tires and a heavy vehicle like yours you are going to need to a have an extra 4L60e on standby. I saw a YT video on a builder and he mentioned 6,000 lb as the limit for the 4L60e. This is a built unit. He didn't mention towing or anything else.

Overlander vehicles are heavy, right? You are going to be doing like a SAS swap and that type of rig? Even if not, winch, large tires, lockers, gear, etc. is going to tax your drivetrain. Maybe not? I don't know what you have in mind.

Just throwing more options for you.

 

[MMcc]

drive shaft U joints and transfer case rebuild

oh I dont know about that! haha at least they can come back out fairly easily. crossing my figures I don't regret skipping this one

 

[MMcc]

AlpineCrick -- I think you're service intervals / replacement volumes sound wise. And if I stick to those (and the 1k mi break-in filter change), I think I'll skip the inline filter. But then again, they cost like 1% of the whole job. Cheep insurance or just another point in the system to leak?

A Beast style sunshell is a must.

"Upgraded" sunshells sell for ~$30 everywhere online and BEASTs are ~$130. I'll call a couple of these ReMan companies and see if they'll make that change for me. The idea of opening up a fresh tranny to swap the sunshell is a bridge too far for this shade tree mech.

"extra" work for me was to swap to a 4L80e, LOL.

4L80E or a manual conversion looks great! No time or space to take on that project right now- maybe once this next one fails- ya know, right after that SAS!

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She'll definitely be a porker - maybe 500lbs over stock weight if I make my 3yr goals of rock sliders, winch, onboard air. But to your point, swapping the 3.73s for 4.?? that'd would reduce stress on the tranny? right?

So far I'm up to:
- Rear main seal
- Deep pan w/ drain plug (w/ corresponding deep-pan-filter)
- trans cooler flush
- inline filter (probably)
- temp sensor (only if the tranny comes w/ a test port --any other opinions out there?)

 

[stutaeng]

AlpineCrick -- I think you're service intervals / replacement volumes sound wise. And if I stick to those (and the 1k mi break-in filter change), I think I'll skip the inline filter. But then again, they cost like 1% of the whole job. Cheep insurance or just another point in the system to leak?



"Upgraded" sunshells sell for ~$30 everywhere online and BEASTs are ~$130. I'll call a couple of these ReMan companies and see if they'll make that change for me. The idea of opening up a fresh tranny to swap the sunshell is a bridge too far for this shade tree mech.



4L80E or a manual conversion looks great! No time or space to take on that project right now- maybe once this next one fails- ya know, right after that SAS!

You must be registered for see images

She'll definitely be a porker - maybe 500lbs over stock weight if I make my 3yr goals of rock sliders, winch, onboard air. But to your point, swapping the 3.73s for 4.?? that'd would reduce stress on the tranny? right?

So far I'm up to:
- Rear main seal
- Deep pan w/ drain plug (w/ corresponding deep-pan-filter)
- trans cooler flush
- inline filter (probably)
- temp sensor (only if the tranny comes w/ a test port --any other opinions out there?)

4.10s to compensate for the larger tires, maybe even 4.56s. Yes, I think that reduces the stress on the engine/transmission. As long as you are not doing crazy stuff like hopping off rocks and stuff like that.

Also upgrade to a larger external transmission cooler.

 

[thegawd]

snip

 

[TechNova]

I think if your replacing the transmission fluid every oil change than your throwing out perfectly fine, brand new fluid.

I sure as **** dont have money to throw away. if I did I would use it more wisely. like on body work for the burb. It's never been touched.

Al

the cost is offset by running the engine oil 6-10K miles