New torque converter with new transmission? Need advice.

Vehicle: 1999 Suburban C1500, 5.7, 215k miles, engine is excellent, trans starting to slip 2-3 shift. Temporarily "fixed" by boosting line pressure 20psi with a handheld tuner. Now it doesn't slip anymore even at wide open throttle, but we all know this is probably a temporary thing to buy some time.

Rear gear ratio is a 4.10. I swapped it from the original 3.42 a few years ago.


Assume that I am buying one of the "mild street/strip built" Transmissions with a shift kit, Corvette Servo, upgraded sunshell, etc from somewhere like performabuilt or Finish Line Transmissions, because I have a very hard time finding anybody around here that I trust enough to know how to rebuild a 4L60E.

I will just install it myself, I assume that if I can rebuild the ring and pinion on the rear end, I can handle a simple transmission swap

Main question. Torque converter .

1) Should I plan on replacing this old one that's on here? It does not seem to misbehave at all but it does have a lot of miles on it.

2) If I am going to replace it, what should I consider replacing it with? The main thing I do with this truck is daily drive, and tow a camper. I am a very spirited driver, I like giving my engines a little wide open throttle a few times a week / day / trip / between stoplights / okay all the damn time. it's not like I'm doing brake stands in a Suburban.

I'm assuming I want something with a low stall, since obviously I'm not launching this thing at a drag strip. should I just stick with a factory stall? Are there other characteristics in a performance TC that i need to look for?

I would replace the converter when you do the swap. It will have nasty bits of everything from you old trans in it. I would hate to reuse a old converter and have it take out a new trans. As for what kind of converter I have no idea of what you should use. Also remember to flush your trans cooler and lines before you hook up your new trans.

X2, I would replace it for peace of mind in regards to debris.

Honestly I'd go for the cheapest stock replacement you can find. I will always recommend dumping as little money into a 4L60E as possible. In fact if you're set on sticking with a 60E I'd at least consider a junkyard unit. You could probably score one for $500 or less with a converter included.

df2x4 said:

X2, I would replace it for peace of mind in regards to debris.

Honestly I'd go for the cheapest stock replacement you can find. I will always recommend dumping as little money into a 4L60E as possible. In fact if you're set on sticking with a 60E I'd at least consider a junkyard unit. You could probably score one for $500 or less with a converter included.

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This truck is a family hauler so I'm a little reluctant to grab a boneyard deal unless I know it's a very low mileage one.

I do appreciate the advice though.

I'm leaning toward one of the lower prices transmissions from Finish Line or Performabilt , at least those tend to come with the basic upgrade parts. Not the cheapest route but I still think it can be kept to about 2 grand.

If it's a family vehicle go with a stock or a s10 4.3 converter. The S10 converter will give between 1800 to 2200 stall depending on your motor. Definitely need a new one with the new trans. Find a small shop to rebuild your 60e. Ppl talk bad about it, but in reality it's one of those things you REALLY need to know what your looking for when rebuilding. If you find a builder who is reputable on this trans, it'll last and last.

Change the converter like the others have said, debris in the old one could take out a new tranny plus most shops won't warranty without a converter change and even a cooler change sometimes. If your trans uses the 298mm torque converter then the torque converter from a 95+ S10 with the L35 Vortec (4.3) engine would seem to be a good choice according to some posts. The GM part number is/was 24202310 (DBLF is the 4 digit alpha code).

So I'm hearing you guys about this S10 TC .

How does that change the way these heavy beasts drive around town, and towing?

I really appreciate all the help you guys are giving me here.

It allows the engine to get further into the powerband on takeoff thus making it seem more “spirited”

It's too bad you don't have a family member in Omaha, driving to SC for your birthday. I have a 4L60e complete fresh remanufactured from Certified Transmission with 2,300 mile on it. Certified is local but has contracts with ACDelco, Ford, C6 used in airport tractors, imports, sticks and many others. The best parts with updates are installed as they also rebuild the torque convertor in-house. They use a carbon fiber compound lockup friction for PWM TCC in the convertor. Their rebuild operation covers 3 acres and international sales. I know 3 techs who worked there and has a tour several times. A cool thing, the build tech gets a bonus if it passes the dyno, the dyno tech get bonus if it fails. They have 7 dyno setups. Torque convertor is married to trans before it leave the build station. The trans I have came out of my son's 03 Tahoe after hitting black ice and sideways into an oak. Just had it installed. At least he quit totaling mine as he did with 3 others.
Yes, clean the cooler lines with flush and as others pointed out, there is no way to get any particles out of the torque convertor, unless you cut it open on a lathe. It's 2wd, don't know what you have. $700 with gear switch, tail-shaft housing, VSS on sitting on pallet. Best of luck!

where are you in SC? I have a transmission shop here. maybe I can help,,,,,,,,,,,