4th Gen 4L80E Shift Lever & Bracket Mods
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4th Gen 4L80E Shift Lever & Bracket Mods Just an overview of the modifications I make to get the shifter geometry perfect.
I use a "Short Style" Sonnax 38511-03K manual shift shaft that is intended to convert later '95 & up 4L80E cores for use in '91-'94 trucks, The issue is.....'91-'94 trucks used a Linkage & Bell-Crank shift mechanism & is clocked wrong for shift cable applications. While '95 & up trucks used a Shift Cable & the manual shift shaft is clocked correctly.....It's too long for 4th Gen's because the neutral safety switch is mounted over it in the truck application.
You will need 2 shift levers unless you want to do a lot of "filling" with a welder.....I hate doing that & avoid it whenever possible, You can get an extra shift lever off ANY GM rear drive car that uses a shift cable.....Even the 5Lx0E & 6Lx0E units.
Shift Cable shift shafts are clocked like this, The picture is of a 2004 4L80E......4L60E's are clocked like this as well.
Sonnax 38511-03K & stock early 4L80E shift shaft's are clocked like this
Take the "extra" shift lever & cut it at the Black Line, Using a bench grinder or angle grinder remove the extra material 'til the part that fits the shift shaft is completely round....Red Line.
Take your original shift lever & Measure the overall length....Write it down!
Cut the shift lever at the Black Line, Again....Using a bench grinder, Remove material a little at a time 'til the 2 pieces together are the same length as the original shift lever. The Red Line gives you an idea of how to grind it.
I use a "Short Style" Sonnax 38511-03K manual shift shaft that is intended to convert later '95 & up 4L80E cores for use in '91-'94 trucks, The issue is.....'91-'94 trucks used a Linkage & Bell-Crank shift mechanism & is clocked wrong for shift cable applications. While '95 & up trucks used a Shift Cable & the manual shift shaft is clocked correctly.....It's too long for 4th Gen's because the neutral safety switch is mounted over it in the truck application.
You will need 2 shift levers unless you want to do a lot of "filling" with a welder.....I hate doing that & avoid it whenever possible, You can get an extra shift lever off ANY GM rear drive car that uses a shift cable.....Even the 5Lx0E & 6Lx0E units.
Shift Cable shift shafts are clocked like this, The picture is of a 2004 4L80E......4L60E's are clocked like this as well.
Sonnax 38511-03K & stock early 4L80E shift shaft's are clocked like this
Take the "extra" shift lever & cut it at the Black Line, Using a bench grinder or angle grinder remove the extra material 'til the part that fits the shift shaft is completely round....Red Line.
Take your original shift lever & Measure the overall length....Write it down!
Cut the shift lever at the Black Line, Again....Using a bench grinder, Remove material a little at a time 'til the 2 pieces together are the same length as the original shift lever. The Red Line gives you an idea of how to grind it.
Last edited by clinebarger; Oct 14, 2017 at 11:31 PM.
Thread Starter
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Joined: Jan 2015
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From: Fort Worth, Texas
-Take the Shift Cable Bracket & cut the REAR bolt hole off, Leave the front hole alone!
-Adjust the Shift Cable to HALF of it's total adjustment....This will allow ample room both ways to make final adjustments.
-Install the "round" shift lever piece that you made on the shift shaft & snug the nut down.
-Insert the "Ball Stud" end of your original shift lever that you modified into the shift cable end.
-I do all mock-up with the shifter & trans in PARK, All photos taken are in PARK as well!
-Put the two shift lever pieces together & TACK them together with a welder, It has to be strong enough to check ALL shift detents......
This is easier with the pan off the trans so you can see the detent roller & rooster comb/detent lever.
-Check that each shifter position lines up with the detents in the trans.
This picture is before ANY mods other than making the shift cable bracket fit.
The Black line is where the Sonnax 38511-03K makes the shift lever end up in park, The Red Line is approximately where the shift lever needs to be rotated to.
The Red Arrow shows where the cable bracket needs to be cut.
A picture of the 4L60E that was in my car.....To show that the shift lever is at about a 45 degree angle in Park
-Adjust the Shift Cable to HALF of it's total adjustment....This will allow ample room both ways to make final adjustments.
-Install the "round" shift lever piece that you made on the shift shaft & snug the nut down.
-Insert the "Ball Stud" end of your original shift lever that you modified into the shift cable end.
-I do all mock-up with the shifter & trans in PARK, All photos taken are in PARK as well!
-Put the two shift lever pieces together & TACK them together with a welder, It has to be strong enough to check ALL shift detents......
This is easier with the pan off the trans so you can see the detent roller & rooster comb/detent lever.
-Check that each shifter position lines up with the detents in the trans.
This picture is before ANY mods other than making the shift cable bracket fit.
The Black line is where the Sonnax 38511-03K makes the shift lever end up in park, The Red Line is approximately where the shift lever needs to be rotated to.
The Red Arrow shows where the cable bracket needs to be cut.
A picture of the 4L60E that was in my car.....To show that the shift lever is at about a 45 degree angle in Park
Thread Starter
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Joined: Jan 2015
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From: Fort Worth, Texas
After everything is mocked-up & double checked for correct function....
-Fully weld the shift lever together, Clean up the welded areas & make sure the weld beads do not interfere with the pan rail.
-Weld a 5/16" washer to the end of the bracket, Tack it first & check fit!
Clean up the welds with a sanding disk so the bolt & sits flush on the washer & the bracket sits flush against the pan rail.
I broke my last sanding disk & it was late.....So I ground the the weld smooth on the side that goes against the pan & machined some "stand off's" to sit flush against the bracket & tack welded them on.
You may want to "Section" the Cable Bracket to keep the welding away from the bolt holes
Modified shift lever (Left) next to a stock shift lever (Right)
Modified Cable Bracket
All together & adjusted, Works perfect, No money spent other than some paint & electricity!
-Fully weld the shift lever together, Clean up the welded areas & make sure the weld beads do not interfere with the pan rail.
-Weld a 5/16" washer to the end of the bracket, Tack it first & check fit!
Clean up the welds with a sanding disk so the bolt & sits flush on the washer & the bracket sits flush against the pan rail.
I broke my last sanding disk & it was late.....So I ground the the weld smooth on the side that goes against the pan & machined some "stand off's" to sit flush against the bracket & tack welded them on.
You may want to "Section" the Cable Bracket to keep the welding away from the bolt holes
Modified shift lever (Left) next to a stock shift lever (Right)
Modified Cable Bracket
All together & adjusted, Works perfect, No money spent other than some paint & electricity!
