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4l80 ?

hookedup50

Active Member
Messages
802
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150
Location
MA
its time to change out my cooked trans. I'd like to get a core rebuilt and have it ready so when I pull the old one out, I have one to immediately install. My truck is a 97, what years are a direct swap? I mostly find 99 and up and the local wrecking yards want to much for a core. What is a reasonable price for a core? I already got the Yanks torque converter like Warwagon has I. One of his trucks. Thanks in advance
 
97+ all pretty well swap in directly. Not sure as to the bellhousing though on 4l80e's from behind a 6.0l as thete has been some differences in the depth of the bellhousings on the ls engines vs conventional 90 degree v8's. Any 4l80e/4l85e trans from 97+ from behind a 350, 454, 6.5l, or duramax will bolt right in. 95-96 can also work, but would require adapting the trans cooler lines(91-96 is known as the front oiler as noth cooler lines hook up in the front, 97+ are rear oilers as one cooler line hooks up in front, one in the rear, and they're 3/8" instead of 5/16"). The mid 99+ is the netter trans as it got all of the factory improvements like the wider band and solud input shaft with the 06+ from a duramax being the absolute best 4l85e trans gm put out(it's the same trans as the gm performance parts 4l85e).

Edit: just did a search and it says so long as you use the correct converter, the ls 4l80e can also be used. The catch is you may only be able to use 5 bellhousing bolts instead of 6 as gm started using the very top mounting hole for the ls, and omitted the one at the 1:30 pisition because of using the top bolt hole.
 
Does anyone know if spline count changed after 99 on the output or mount holes for the transfer case. I looked online and its generic info. Also I have choice of l480 or l485. Im inclined to go stronger. but is it worth 200 bucks on a truck that only puts out so much torque?
 
Pretty sure there is 2 different output shafts that were used. Up to 00 they were all 32 spline outputs, but sarting in 01 the 4l80e or 4l85e in a 3500 truck had the MUCH larger 29 spline output shaft. All the actual mounting flanges for the transfer case are supposed to be the same for GM, just makesure it has the 32 spline output shaft in it. As to 4l80e vs 4l85e, there are some improvements in them, but for no more power than a 6.5l puts out, it isn't really needed. The torque rating only goes up a little, but the primary differences are more gears in the planetaries, and I believe the 4l85e had straighter cut gears in them vs the 4l80e. It made them slightly louder, and only slightly stronger. If you can get one from a late 99+, the improvements in them is worth it. And reman torque converters are not that expensive. Last I heard, people were buying the transtar billet cover single disc for well under $500 with core(heard a few have found them for $325, but I can't confirm this personnally), so if it comes from a 6.0l or something else withahigh stall converter, it isn't the end of the world to get another converter.
 
Thanks again Ferm. Both trannies came out of a 2500, but will check spline count before purchasing. My plan is to install this tranny with new converter and rebuild the one in the truck and put it into inventory for insurance. With my other vehicles I have doubles of everything, so when stuff breaks, i have it waiting to be reinstalled.
 
I think the 32 spline is roughly 1.25", and the 29 spline is 1.44". It's a noticeable difference just by looking at them. Theres not many of the 4L80E's with the 29 spline output in them, but enough for GM to make you pull your hair out.
 
Yes it is, I have a talent for purchasing things with different splines. Mostly on my jeep with parts from every manufacturer and my datsun with 3 different drive shafts.
 
I presented myself to the transtar warehouse and from what i gather is they only sell to shops.They sold me a billet gm88-bp for 189 instead of the 325 quoted over the phone. I was told to talk the salesman into them selling me a rebuilt 4l80e in the same manner, or use my ST1 tax number for my regular business. Now to order braided cooler lines.
 
I have a disconnect set for fuel lines. Is there a different disconnect tool needed to remove the cooler lines off the transmission?
 
Does anyone know the male thread size going into the tranny cooler and radiator. I'm assuming its metric and not NPT . I bought stainless braid lines assuming the kit would have the adapter like Leroy would include.
 
That's definatly what they are. Finding an adapter is going to be an issue. Hopefully a hydraulic shop has some.
 
I'm ready to yank the tranny and Tcase(all bolts removed). I remember War Wagon asking this question and I believe I remember the answer. Do I have to break the Tcase to get it out because of the torsion bar support. It looks like it can be done intact by pulling unit forward and tilting it out. The slip yolk tailpiece is the clearance issue. After this project I'm buying a rotary lift
 
One more question.... Does the shifter linkage just pop off with a small pry bar without ruining it? Im pretty old school and on my Chrysler TF tranny you would slide the outer casing back to release it from the ball. This has those plastic tabs that remind me of that brakake light switch that gave me fits in the cab.
 
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