Need help with Transmission rebuild parts GM4L30E

[Oro_O]

1998 Acura SLX (trooper), w/GM 4L30E transmission.

The fluid was replaced six weeks ago and despite a new crush washer torqued properly, the washer weakened and started a drip that was not caught until it was over a quart down. According to an expert on this unit, the 3rd gear clutch burned up. (New fluid was dark brown and slightly burnt; no go in 3rd gear). The unit had 162k on it and worked perfectly prior to this; I had always been careful about maintenance and am very, very disappointed (and pretty surprised) in myself that I did not catch this in time. I am also surprised being 1.5 qts down could destroy a clutch; but I am not an automatic transmission guru/expert.

I have no experience rebuilding a transmission so here goes. I asked at the Isuzu forum about what kit, parts to get but got no replies. Here's what I am thinking:

New Rear main seal for engine while transmission is out,
rebuild kit for tranny w/clutch discs (plates, too? other parts?)
New torque converter
ATSG service manual for the 4L30E

Other than that and a lot of alcohol (joke), should I be thinking of anything else?
I am unclear about the plates - do I need them or...? One thing I read said to media blast and then hit with 200 grit the existing plates. Is that good or...?

I am looking at these items:

TC's:
https://www.rockauto.com/catalog/x,carcode,1313393,parttype,8668

Kits:

https://www.rockauto.com/catalog/x,carcode,1313393,parttype,8512


I could use some advice here. Which kit? Any difference in those brand rebuilt TCs (Alliance vs. DACCO)? I will have my dad looking over my shoulder and helping me where needed and with fabbing tools - welding together a spring compressor, tranny stand, etc. (He's good at that). I am thinking besides cleaning the valve body, I'm not going to mess with that since it was working fine and has been maintained with good fluid. Plus, if something goes wrong there later, I can service it with the unit in place.

Here was the original thread at the Isuzu site and the advice I got there, but it's dried up now and I need to get the parts ordered so I can get started on it next Monday.

Transmission failure thread at planetisuzu

 

[Merkava_4]

Originally Posted By: Or
ATSG service manual for the 4L30E


If you weren't in such a hurry to get everything together before next Monday, I'd say get ahold of that manual first and read it. It might have some suggestions for special tools that you'll need for the rebuild.

 

[Oro_O]

That is not a bad idea, but I have an ok handle on that from some online-write-ups on rebuilding from the Isuzu and BMW forums (this went into a large number of 3 and 5 series BMWs, too), and there is a separate online manual on re-assembly from a guy in NZ. Also, it's going to take me a day or two to even get it out, and I have my retired dad to work on those things while I'm removing it from the vehicle.

 

[Texan4Life]

If your in a rush to do this at all. do yourself a favor and just get a reman transmission. I installed my first reman and what a load off the shoulders being able to drop one and put in another.

I highly recommend getting the rebuild manual and looking into it before going any deeper. Not sure who ATSG is, but if possible I would try and get a factory service manual.

Take tons of detailed pictures as you disassemble, this will help in reassembly later, especially if life gets in the way and it doesn't get done as fast as you would like...plus sharing a few pics is always welcome here on the forum

Also you'll need some basic measuring instruments like calipers, dial indicator, magnetic indicator holder/base, and maybe even some feeler gauges.

 

[clinebarger]

Originally Posted By: Or
I have no experience rebuilding a transmission so here goes.



I have built thousands of transmissions, But never a French HydraMatic 3L30/4L30E. They are pretty rare in North Texas.

Your "Kamikaze" approach will most likely end with you taking it to a professional.

 

[Oro_O]

Originally Posted By: Texan4Life
If your in a rush to do this at all. do yourself a favor and just get a reman transmission.


I understand your point but these aren't as cheap as other GM units, and the added cost isn't an option right now ($2k for reman I install, $250 to do a rebuild myself) . I have the requisite skill to give it a try, a good workshop, assistance (my dad will be in the other garage bay 10' away finishing a restoration on a '48 Ford 8N), and available online expert assistance if I get stuck. I have time to do it (budgeting 5 days w/more available) and can let it sit if I run over and have to finish later. I did look at other options and I found an 02 with a blown motor and a one year old reman'd tranny for sale. But there were TC and valve body changes in between that make the swap impractical because of wiring and electronic issues. We were going to take the trailer and go get that one but then found the issues when double-checking.

Quote:
I highly recommend getting the rebuild manual and looking into it before going any deeper. Not sure who ATSG is, but if possible I would try and get a factory service manual.{\


ATSG is Auto. Trans. Services Group, trade association for transmission service/repair. Their books are the bibles for the ones they cover, and they have one for this unit. And I will have one other assembly guide as a cross-reference.

Quote:
Take tons of detailed pictures as you disassemble, this will help in reassembly later, especially if life gets in the way and it doesn't get done as fast as you would like...plus sharing a few pics is always welcome here on the forum

The new iPhone 5S will be real handy here! I will post follow up notes and some pics here and the Isuzu forum.

 

[Oro_O]

Originally Posted By: clinebarger


I have built thousands of transmissions, But never a French HydraMatic 3L30/4L30E. They are pretty rare in North Texas.

Your "Kamikaze" approach will most likely end with you taking it to a professional.


There are no Isuzus or BMW 3 or 5 series built between 1990 and 2005 in North Texas... ? Odd...

And wow, you really have little tact or appreciation of someone taking a thorough approach, preparing, and seeking advice. I do have, as mentioned, a lot of vehicle experience, and copious (expert) assistance, and references. Well equipped shop, and time. There are well documented examples of people with less, following the manuals well and getting great results. I'd hardly characterize anything like that as "kamikaze" unless I was just an ornery old a**hat with a little too much to drink before spouting off late at night. But then, it takes all types to make the world go 'round...

 

[JTK]

Back when I was quite involved in anything Isuzu Rodeo/Trooper, we'd chat about servicing the 4L30E, but problems with them were rare. We had several early 2000's Rodeos and Troopers in the family at the time. All but one had the 4L30E. The 2003 Rodeo 4x4 was a 5spd. All the 4L30s of that time were "sealed" with two plugs on the main pan. One for filling and checking level that was stamped up high on the pan, the other for draining.

Anyway.. The most common cause of shifting issues with them was the range/mode sensor. The switch on the gear shift shaft that would tell the dash and powertrain computer what gear the driver selected. If the PRND321 lights are acting up on the dash, the thing will shift like poop.

200K miles wasn't unheard of for a reasonably maintained 4L30E, but at your mileage, I'd buy a new/rebuilt one, or a low mileage used maybe.

They are odd beasts. Basically a 3L30E, with an adapter case added onto the input end for the 4th gear. This is why there's two pans on this trans.

 

[Stag]

Oro, I can't help you with what parts to buy. I will/have attempted a lot of things on my cars, but I feel AT rebuilds require more tools, skills, precise measurements, attention to details, and a cleaner work environment than I can possibly provide. I saw your posting on Planetisuzoo, but didn't think I could provide much more help than those folks until now. I haven't seen anything here about whether or not you have the correct light indicators glowing on the dash and whether or not they match the selector lever. The Range Mode Switch is a vital electronic piece added on that is a common source of trouble. The seal on the selector shaft behind that switch begins to seep ATF while the car is running, and gets into that switch causing it to lose continuity, especially in the lower gears that folks usually don't move the switch to. It is relatively easy to remove and clean that; and replace the seal behind it.
And, again, are you filling the trans fully by using the proper procedure?
If you do choose to rebuild, I wish you luck. I know some folks have done it over at the Zoo. It does sound like an enlightening father/son project.

 

[clinebarger]

Originally Posted By: Or
Originally Posted By: clinebarger


I have built thousands of transmissions, But never a French HydraMatic 3L30/4L30E. They are pretty rare in North Texas.

Your "Kamikaze" approach will most likely end with you taking it to a professional.


There are no Isuzus or BMW 3 or 5 series built between 1990 and 2005 in North Texas... ? Odd...

And wow, you really have little tact or appreciation of someone taking a thorough approach, preparing, and seeking advice. I do have, as mentioned, a lot of vehicle experience, and copious (expert) assistance, and references. Well equipped shop, and time. There are well documented examples of people with less, following the manuals well and getting great results. I'd hardly characterize anything like that as "kamikaze" unless I was just an ornery old a**hat with a little too much to drink before spouting off late at night. But then, it takes all types to make the world go 'round...


I have quoted a few rebuilds on them, But no takers. I do not see them often, Never said they don't exist here. Said they are rare....Even rarer for someone to put money in one. I bet there are tons of Subaru's in your part of the country too....But not here!

Good luck on your build, I wasn't trying to be tacky, But...Throwing clutches & seals in a trans IS a Haphazard approach. You are assuming the low fluid level caused the clutch pack to burn up & Not Poor line pressure rise, Leaking apply circuit, Valve body wear, Boost valve wear, Cross leaks, etc etc.