Factory Squarebody 4L80E shift linkage picture request

[Larry]

Anyone have factory 4L80E square body shifter linkage pictures from a 1991 Suburban or Crew Cab they can share? Or better yet….anyone have the goods for sale?

The reason I ask is I’m doing some cleanup on a friends Suburban that recently went from a 6.2L/700R4/NP208 to an L29 454/4L80E/NP208 combo. The first order of business was to get the transmission to shift correctly as it was using a Dakota Digital pulse generator and interrace module and either was defective or something as the broadcasted speed to actual speed was around 32 MPH off. I end up getting my hands on a prototype kit to convert the original 208 from a cable to run an actual VSS sensor by using a NP261 reluctor ring and early style VSS sensor. It works great and now the ECM is seeing actual VSS speed within 3 MPH of GPS but the trans has other issues that I am dealing with now (dead 1-2 shift solenoid).

The second cleanup project was to correct the actual transmission shifter operation. When they swapped in the 4L80E they could never get the shifter to work correctly so they went to the aftermarket to make their lives worse by using a Lokar transmission linkage. That thing didn’t work worth the crap either as it was barely go in Park and 1st gear couldn’t be reached so I reworked the original linkage by moving the frame bracket back a few inches and shortening the stem that goes into the frame bracket. It works 100% better now but still doesn’t satisfy my OCD as it is harder than I prefer to pull out of Park but at least all ranges can be reached now. The PRNDL in the cluster is not accurate either and that drives me nuts. Its accurate in the middle quadrants (R N D) but Park, 3, 2, 1 are off as if the 700R4 PRNDL and 4L80E range are not linier. I suspect it is hard to pull from Park as the Z-bar and shift rod are completely straight where there is a serious breakover angle to get the Z bar to move the selector shaft into R. In fact, it won’t even go from P to R because it pops out of P so violently the lever lands in N or D then you have to move it back to R. There must be a unique shift linkage Z bar and possibly rod and even dash PRNDL for a 1991 squarebody with a 4L80E so with that, I’m looking for pictures to see what I need to modify or better yet….parts to correct this. Using an aftermarket shifter is not an option. People that know me know I am not a fan of aftermarket pieces unless its something that truly makes the vehicle better like ORD goodies, or this here VSS kit

Here is the patient

And here are the details of the NP208 VSS conversion using a NP261 reluctor. This kit is available from Walters Engineering and Performance. They also offer a kit to convert a NP241 to VSS as well. This kit is a game changer for 4x4 engine swappers that need a VSS in an older 208 or 241 without the need to use any hoekey pulse generators and finicky interface modules. They currently do not have anything for a 205 yet as that one is a real challenge with such a small hole in the tcase rear housing where the speedo adapter lives but possible one day they will.

Pictures from beginning to end........

NP241 VSS Sensor and pigtail

 

[mrk5]

@1-ton is the only user I can think of that has a '91. It's a V3500 crew cab, I just don't remember if it's an auto or manual.

 

[mrk5]

Just remembered @HankScorpio has a '91 V3500 as well.

And @obijuank5 has a '91 V3500.

 

[HankScorpio]

My '91 V3500 is a manual, SM465/NP205 so no help there. I have an ORD VSS in my '90 Blazer after swapping to a SM465/NP205 combo. Looks like the same stuff as your NP208 conversion. Had to have them machine the housing to fit the VSS and then plug the stock speedo hole. I had thought it was a reluctor from a 241 but could very well be the same 261 part machined to fit. Pics look similar.

Labor to Machine Customer's NP205 Speedometer Housing for GM VSS, Tone Wheel, Plug, Speed Sensor and Pigtail Included

Labor to Machine Customer's NP205 Speedometer Housing for GM VSS, Tone Wheel, Plug, Speed Sensor and Pigtail Included Return shipping is calculated in cart. Shipping from you to us is not included. Please ship with all your contact information included and/or a copy of your order. Shipping...

www.offroaddesign.com

 

[Larry]

My '91 V3500 is a manual, SM465/NP205 so no help there. I have an ORD VSS in my '90 Blazer after swapping to a SM465/NP205 combo. Looks like the same stuff as your NP208 conversion. Had to have them machine the housing to fit the VSS and then plug the stock speedo hole. I had thought it was a reluctor from a 241 but could very well be the same 261 part machined to fit. Pics look similar.

Labor to Machine Customer's NP205 Speedometer Housing for GM VSS, Tone Wheel, Plug, Speed Sensor and Pigtail Included

Labor to Machine Customer's NP205 Speedometer Housing for GM VSS, Tone Wheel, Plug, Speed Sensor and Pigtail Included Return shipping is calculated in cart. Shipping from you to us is not included. Please ship with all your contact information included and/or a copy of your order. Shipping...

www.offroaddesign.com

Ah, ya! That's cool and very similar method except for the maching portion. I don't run VSS on anything of my own so I wasn't familiar with ORDs 205 solution. Good to know though!

 

[Capt Ron]

I got a 4l80 out of a 91 burb a while back. Think I might have even sent you pics from the wrecking yard as I was pulling it.
I think I got the shifter mech but not sure. If I did grab it I probably put it with all of my other shifter stuff thinking they were all the same. I'll check asap.

 

[Larry]

I got a 4l80 out of a 91 burb a while back. Think I might have even sent you pics from the wrecking yard as I was pulling it.
I think I got the shifter mech but not sure. If I did grab it I probably put it with all of my other shifter stuff thinking they were all the same. I'll check asap.

I'll have to go through text messages and see if you did. I can send you pics of the typical z bars if you look through your pile to find one that's not like the others. Lol

Thanks Ron!

 

[obijuank5]

It's just like the rest but about 1/2" longer on the long rod.

 

[Larry]

It's just like the rest but about 1/2" longer on the long rod.

Curious what you mean by the rod is longer. I don’t see a longer rod from the column to the Z bar making a difference as rod length doesn’t seem to be an issue....perhaps the rod needs to be longer after the Z bar is modified. You can see there is 1.5” of rod sticking out past the connection to the Z bar now so its not too short.

What I feel is the biggest issue is the rod and Z bar are perfectly straight, which causes a major binding break over angle to get it out of Park. It seems the Z bar needs to be modified to allow more leverage of the rod to move the Z bar. I could see the rod might need to be extended at that point. I have a few Z bars and rods laying around to cut up to modify it but I’d sure like to see an stock 1991 set up to see what I should aim for.

 

[Wes Harden]

Not that I know if it make a difference, but is the bracket on trans selector shaft on correct.
What if you turned the z bar over and had it go up instead of down. A longer bar to column would then be needed I think.

 

[Larry]

Not that I know if it make a difference, but is the bracket on trans selector shaft on correct.
What if you turned the z bar over and had it go up instead of down. A longer bar to column would then be needed I think.

That's a good point. I has the 700R4 selector bracket on it now but he does have the 4L80E selector bracket and I do recall those being offset. I'll give that a swap and see.

Good idea

 

[Larry]

Not that I know if it make a difference, but is the bracket on trans selector shaft on correct.
What if you turned the z bar over and had it go up instead of down. A longer bar to column would then be needed I think.

You’re bringing up the selector shaft bracket was a great idea .

I put the 4L80E selector shaft bracket back on and it changed the angularity of it all where the rod and Z bar are not perfectly straight anymore. The angle of the dangle isn’t bound up now and it seems to shift through the range just fine. Pulls out of Park super smooth now! I have the steering gear off of it now so I can’t start it to run through the ranges but it feels right. The PRNDL still looks off but I might be able to adjust it to be a little closer to correct.

Bueno! In all reality, it looks l like all that needed to be done from the beginning is move the frame bracket back about 1.5”s or so

700R4 bracket on a 4L80E is no Bueno

Shit like this is why I stick to manual transmission!

 

[Wes Harden]

There is a cable that connects the prndl to the lower shift bowl on the column that should be able to fine tune the indicator.
Figured it would be something simple. Glad you got it

 

[Larry]

Steering box back on and test driven. The selector shaft bracket corrected everything and PRNDL adjusted. The shifter linkage works smoooooth now and the PRNDL range is correct. Feels like the 4L80E has pretty soft detents in it. Definitely smoother than the notchy 700R4 before it.

Case closed….Everyone can go back to sleep now

 

[folkenheath]

You’re bringing up the selector shaft bracket was a great idea .

I put the 4L80E selector shaft bracket back on and it changed the angularity of it all where the rod and Z bar are not perfectly straight anymore. The angle of the dangle isn’t bound up now and it seems to shift through the range just fine. Pulls out of Park super smooth now! I have the steering gear off of it now so I can’t start it to run through the ranges but it feels right. The PRNDL still looks off but I might be able to adjust it to be a little closer to correct.

Bueno! In all reality, it looks l like all that needed to be done from the beginning is move the frame bracket back about 1.5”s or so

700R4 bracket on a 4L80E is no Bueno

Does anyone have a source for this selector shaft bracket for a 4L80E? Or what it came off of?

I have mounted a 4L80E and have it all working almost correctly, without finding this thread I had moved the pivot bracket back on the frame and also modified the angle of the Z bar looking piece so it would shift in and out of all gears.

However, when you do that, it won't start in neutral, it will start in 4th gear, because of the column detent mechanical neutral safety. I have lengthened and shortened the Z bar, and tried different adjustments, and everything creates a new problem.

It started out not going into manual low. I fixed that moving the pivot back and shorter linkage.

Then it would start in 4th gear. So I readjusted it so the trans detent and column detent are in neutral at the same time, and then its back to not going into manual low.

So I made the Z bar pivot shorter yet. That fixed the manual low issue, and the mechanical neutral safety works correctly.

However now it travels too far going into park and it won't lock in the column. The pivot needs to move it farther in the gear direction than it does toward park, and this looks like it would solve the problem by having two different pivots that are peaked at different angles.

I just need to know where or if I can get a couple of them. Thank you.

 

[centexk5]

Same question here.

 

[1-ton]

@1-ton is the only user I can think of that has a '91. It's a V3500 crew cab, I just don't remember if it's an auto or manual.

What kind of bracket for shift linkage can depend on whether the 4L80E transmission you have is a later model trans with a long shaft, or an early model trans with a short shift shaft. All the square bodies that came with a 4L80E trans where early model transmission with short shaft.

 

[folkenheath]

I fixed it myself Tuesday after seeing Larry's picture of the bracket he used, I don't know what it came off of and that's what I wanted to know, but while viewing the picture a 2nd time I realized it wouldn't fit my short selector shaft transmission. (I see now 1 ton also mentioned this above).

I also realized sourcing a bracket from a 1991 crew cab or 2500 burb with a short selector shaft was going to be difficult from only one model year.

My solution was to take this...(I believe to be from a 1994 K2500 4L80E)




and make this....





I just cut the center bend out, notched the corners, rotated it 90 degrees and welded it back together with the slotted bracket on top the other portion slightly. It cleared the trans pan on the short tailshaft and functioned correctly. I did also have to shorten the center to center length of the Z bar pivot from 2 3/4 to about 2 1/2".

Now it goes into every gear position and that neutral safety detent in the column works correctly.




Even thought there shouldn't be much bending force in that direction, I will add two small triangle braces.

 

[1-ton]

Short shift shaft is the only 4L80E shaft that works with a square body. I think the short shaft 4L80E was up to 1993 or 94. After that they went to long shaft. I think it was 2006 when the 4L80E went to rear lube port at the center support, and you would have to modify the transmission cooler lines for a square body as well.

 

[folkenheath]

@Larry installed a long selector shaft 4L80E in a square body above, I would still like to know what that selector shaft bracket came out of for those swaps?

I had to modify the tranny cooler lines anyway even from a TH400 to pre '97 4L80E swap because they were a bit further back, I think the locking converter takes more room in the bellhousing area. All 97 and up 4L80Es have the center support lube return, but I wouldn't let that scare you from the swap, that's one of the easier fixes.

The transmission case itself is only 1 5/8" longer than a TH400. In a 2WD tailshaft application the difference is more than that.

I would also still like to see a picture of an original 1991 square body 4L80E selector shaft bracket and Z bar assembly. Because it would of had a short selector shaft and the bracket would have to be slightly different than what Larry used.

I did move the factory Z bar pivot. I simply moved the front mount bolt to the rear factory hole in the frame, and drilled one more hole in the frame for hte rear mount bolt.