kv11111

Can someone tell me the difference between a ls and non ls 4l60e? I bought a non ls for dirt cheap, would like to rebuild it for my truck, which I know is an ls. I know the bolt pattern on the bell housing is different, but are there other things different, thanks.

mrvedit

First, if it is a '94 or '95 trans, walk away as the valve body will be incompatible with any LS engine PCM. I call them the alpha and beta test years to be avoided unless you are stuck with a '94 or '95 LT engine PCM.

However, if it is a '96 or later, it can be used.

Here are some threads in which I document the differences:
https://ls1tech.com/forums/automatic...uld-i-buy.html
https://ls1tech.com/forums/automatic...s1-4l60-e.html
https://ls1tech.com/forums/automatic...urus-help.html

The non-LS has a 298mm input shaft and requires an "LT" style converter. Since the LT style converter is shorter, you need to add a spacer on the flexplate to properly support the converter's pilot. Also the converter hole spacing diameter is about 1/16" different due to SAE versus Metric??); this can be addresses by elongating the LS flexplate holes or getting a dual-pattern flexplate.
Here are the parts you need:
12563532 flexplate to crank spacer
19257940 bolts (need 6 bolts)
19260102 dual-pattern flexplate

I warn people about using old high mileage non-LS 4L60E on their LS engines for durability reasons, but if you rebuild it with upgraded parts, it should be fine.

kv11111

Well its from a 97 blazer and I will be doing a full teardown and rebuild on it. What about the stator support or input drum it appears there a differnt sizes available. Thanks mrvedit.

mrvedit

A '97 should be fine as long as your rebuild it and understand it will not directly bolt up, but will with the additional parts I listed.
I am less familiar with non-LS 4L60E. Replacing the stator shaft is a bit tricky; you may want to get a rebuilt pump instead. Either way, compare the length of the new stator shaft with the old one; we recently had a thread where the replacement was wrong, resulting in very strange symptoms.

kv11111

I do have 1 4l60e rebuild under my belt, which included a stator support changeout, so that i can do. I appreciate you getting the part #s for me, that helps a lot.

mrvedit

Understood. When you press in the new stator support shaft, make sure it is precisely aligned with the alignment pin in the pump. If you nick that pin during the press, it will shave off metal which will bunch up under the shaft and prevent it from seating completely square; the result will be rapid wear of the front bushing.
Also make sure the pump half is well supported so that it doesn't bend during the press.
(You probably already know all this, but I write it for the many people that read it in the future.)

PBA

If you install a LT series stator support (shorter than the LS series stator support) and use a LS series torque converter, the stall of the torque converter will go away. I remove everything out of the pump, the PR valve assembly, TCC valve assembly, filter, high pressure pin with spring and checkball. Press out the stator tube, thoroughly clean the pump and all the passages with solvent or mineral spirits, flat sand it on a granite block or glass re-stake the dowel pin and make sure the area around the dowel pin is flat and blow out all the passages with high pressure air. Make sure the stator tube you want to use has the right bushings installed and "dress" the stator tube. Make sure you blow out all the passages with high pressure air. Put the stator tube in the freezer for 3-4 hours. With the pump cleaned out and blown off with high pressure air, put it in the oven at 500F - 550F for 30 - 35 minutes. Have a "dead blow" hammer handy and with the proper heat insulated gloves, remove the pump from the oven and install the stator tube. It should go in easily and over the dowel pin. If there is some resistance, use the "dead blow" hammer and tap it in place quickly. You only have 10 - 15 seconds to do this. Once in place set the pump so it will keep the stator in place and have a fan aimed at it if you want it to cool quickly. Install the stator bolts at 120 inch pounds, re-stake the dowel pin using a large sharp chisel, you only need to hit it a couple of times and then file the area where you used the chisel. Now use high pressure air on the pump and on all the passages and then re-install everything back in the pump. I have never had a problem doing it this or a "cross leak" in the pump doing it this way for the last 25+ years. Make sure the wife is out of the house, the windows in the kitchen open when you do this, as it will smell up the place.

mrvedit

Wow, thanks again for the very detailed instructions!
The freezer/oven method is clever.
Of course, getting the wife out of the house and sending her shopping might make it cheaper to just buy a new pump.

Iroc_Rat

Okay question... I just recently purchased a 5.3 (2001) with computer and wiring harness in which I relabled to work No emissions an no A/C. I also got a (1996) 4L60E, will this computer work this tranny? will it bolt up? or do i need a flex plate an stand alone harness just for the trans? I'm putting this a 1989 Iroc.
Thanks in advance.

mrvedit

I answered this in the other thread were you posted a duplicate question:
https://ls1tech.com/forums/automatic...up-my-ls1.html

(I know you are new here and may not know the etiquette - Please don't ask the same/similar question in multiple threads.)