4L60 Re-Rebuild for my C20

[LTZ C20]

So, got some progress with the rebuild.

All new seals, gaskets, accumulators.


New separator plate.


New pump rotor, vanes and slide. New stock servo, all these parts are cleaned up and ready for assembly.


New 5 pinion rear gear set.


New to me (used) but better than mine input drum.


Ok, that's all I got.

[1967KaiserM715]

Looking good, what's it take, about a week to put together and install? Or you installing yourself?


Sent from my iPhone using Tapatalk

[LTZ C20]

Looking good, what's it take, about a week to put together and install? Or you installing yourself?


Sent from my iPhone using Tapatalk

He said if he worked on it straight thru it should only take about 6 hours but he has family events going on so he's doing an hour or so every day. He did say it should be done this week. I pulled it out myself so I'll put it back in. I thought about rebuilding it myself just to learn but he said he would do it for me so I didn't bother.

[LTZ C20]

Alright Irish, I'm assuming this is the area you meant.



Also, I cut my crossmember to make services easier, no ledge in the way of pan bolts anymore.

[1967KaiserM715]

Alright Irish, I'm assuming this is the area you meant.

Yes, if you can cut the TOP of the 350 tube so the dipstick matches the 4L60, which is around 5/16", that way the dipstick slides in further and matches the 4L60 depth, it should work fine.


Sent from my iPhone using Tapatalk

[LTZ C20]

That's what I was thinking. The "shouldered" area probably won't matter much because the stick will go down further after the tube is cut and I'm putting a deep pan on it.

BUT, the shouldered area creates a calm fluid area so the fluid leaves a level, accurate mark on the stick. If the top of the tube is cut, forcing the stick to protrude further out the bottom, will this expose enough stick to then be in an open area where fluid is sloshing around, being pumped in and out, not calm, causing an inaccurate mark on the stick, possibly different every single time it is checked.

[Irish_Alley]

That's what I was thinking. The "shouldered" area probably won't matter much because the stick will go down further after the tube is cut and I'm putting a deep pan on it.

BUT, the shouldered area creates a calm fluid area so the fluid leaves a level, accurate mark on the stick. If the top of the tube is cut, forcing the stick to protrude further out the bottom, will this expose enough stick to then be in an open area where fluid is sloshing around, being pumped in and out, not calm, causing an inaccurate mark on the stick, possibly different every single time it is checked.

never really thought about that part lol. im not sure how much turbulence the fluid will have but i doubt it will enough to cause a false reading if it does i dont see it being that much off.

[bd]

Why not fabricate and braze a replacement "Y" mounting tab on the original tube to cover the three weld perforations?  It's not difficult to do.

[LTZ C20]

Why not fabricate and braze a replacement "Y" mounting tab on the original tube to cover the three weld perforations?  It's not difficult to do.

It's for an 89 1500, the shape is wrong for the body shape of the truck, it fit before but rubbed the firewall and air cleaner housing, I think flexing finally just snapped the bracket off. The 350 tube is shaped for a 73-87 firewall.

[LTZ C20]

That's what I was thinking. The "shouldered" area probably won't matter much because the stick will go down further after the tube is cut and I'm putting a deep pan on it.

BUT, the shouldered area creates a calm fluid area so the fluid leaves a level, accurate mark on the stick. If the top of the tube is cut, forcing the stick to protrude further out the bottom, will this expose enough stick to then be in an open area where fluid is sloshing around, being pumped in and out, not calm, causing an inaccurate mark on the stick, possibly different every single time it is checked.

never really thought about that part lol. im not sure how much turbulence the fluid will have but i doubt it will enough to cause a false reading if it does i dont see it being that much off.

Well I guess we are going to find out, I just cut 5/16 of an inch off the top of the 350 tube, the bottom of the tube stops halfway between the bottom line of the hot section and the "H" in HOT on the 4L60 stick when it's fully installed in the 350 tube.

[Captain Swampy]

http://www.gopnh.com   Check out these guys for converters. Most places won't warranty a tranny if you don't replace the converter. Look at a cut away view, there are too many places  for debris to get stuck, only to come out later and destroy a perfectly good tranny. No flushing either, they have to be disassembled and cleaned.

[bd]

Also, I cut my crossmember to make services easier, no ledge in the way of pan bolts anymore.

I suggest that you shallow the angle at the ends of the relief that you cut and radius the corners or the crossmember might eventually develop stress cracks radiating outward from the corners.  Removing the entire flange as you have will tend to focus stress and flexing through the narrowed section, and especially around the corners.  Removing some of the flange to gain access for easier service is a great idea, but tapering the ends of the cut and leaving 3/8" to 1/2" of flange outboard of the radius will ensure that cracks won't develop.

Why not fabricate and braze a replacement "Y" mounting tab on the original tube to cover the three weld perforations?  It's not difficult to do.

It's for an 89 1500, the shape is wrong for the body shape of the truck, it fit before but rubbed the firewall and air cleaner housing, I think flexing finally just snapped the bracket off. The 350 tube is shaped for a 73-87 firewall.

Got it.  You could always extend the tube to match the '89 design, but to avoid top-hat seal damage the protruding edge of the tube would need to be slightly radiused.

[LTZ C20]

Yea that's why I'm just getting a new one.

[Captain Swampy]

http://www.jegs.com/i/TCI/890/743865/10002/-1

Is this the tube you need?

[LTZ C20]

Also, I cut my crossmember to make services easier, no ledge in the way of pan bolts anymore.

I suggest that you shallow the angle at the ends of the relief that you cut and radius the corners or the crossmember might eventually develop stress cracks radiating outward from the corners.  Removing the entire flange as you have will tend to focus stress and flexing through the narrowed section, and especially around the corners.

Why not fabricate and braze a replacement "Y" mounting tab on the original tube to cover the three weld perforations?  It's not difficult to do.

It's for an 89 1500, the shape is wrong for the body shape of the truck, it fit before but rubbed the firewall and air cleaner housing, I think flexing finally just snapped the bracket off. The 350 tube is shaped for a 73-87 firewall.

Got it.  You could always extend the tube to match the '89 design, but to avoid top-hat seal damage the protruding edge of the tube would need to be slightly radiused.

The bolt hole that almost lines up with the cut in the flange is for a brace, the end of the brace and cut section should line up just about equal and there are 3 bolts in that 6 inch section. As for doing anymore fabricating, well I already recoated the crossmember so I'll worry about if the issue arises. I look under the truck a lot, keeping an eye on things and when checking fluids and doing services, I keep up on regular maintenance, so I'll keep an eye on it.