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Turbo 400 with Dual Gate adjustment- issue (will roll in Park)
I have a 72 442, 455 with Hurst Dual Gate and Turbo 400. I put a new Dual Gate cable in years ago and lucked into getting all the stops close for each drive setting. I have zero experience with automatic tranny's as far as working on them so getting it close was pure luck. The problem is when in park the car will still roll unless the parking brake is on, and I wouldn't even trust that on a very steep incline! If I look under the car at the lever that the cable end attaches to, does the lever need to move closer to the front of the car? That is what I'm thinking, and I can loosen the bolt and move the arm farther in the proper direction. This is really frustrating me! If only it was a 4 speed! LOL! Any wisdom will be appreciated!
OLE442
Last edited by OLE442; April 30th, 2023 at 09:49 AM.
My lever on the tranny doesn't look quite like the one in the Hurst instruction diagram for adjusting the linkage. It's hard to tell if the tranny is in neutral so, since the linkage was adjusted pretty good except for the park setting. I undid the bolt at the lever and pushed the lever forward and tightened the bolt down. I'll start the car up today with the 2 post lift up a bit so the wheels aren't on the ground. I'll see that way if the different positions on the shift console appear to work and, if so, does it appear to go into Park and does the key come out of the ignition when I shut it down. I'll also check to see if it will start in neutral. If it doesn't work, I'll undo the linkage at the lever and move it slightly back until it all works. The I'll lower the car to the ground and go through the shifter settings again. Maybe after that a run up & down the street if I'm feeling confident. We shall see........
Last edited by OLE442; June 29th, 2022 at 03:07 AM.
Reason: added text
Ok, so there are two systems here. Don't worry about the key, reverse lights, neutral safety switch, whatever. That's the backdrive linkage and it gets adjusted later. The cable from the shifter needs to work, first. You can even temp disconnect the backdrive linkage at the adjustment nut for now. Park on the shifter needs to put it in park at the transmission.
Rusty nut on right can be temp disconnected for trouble shooting. That cable on left is the shifter cable. It rotates that bracket. The rod stuffed through the bracket is also backdrive. You are heading to park with that bracket rotating with the shifter nut coming forward and the back drive linkage lifting up to the pan. Recommend loosening shifter cable, putting the trans into honest to God park with your hand, then put shifter in park, and reattach cable. Then, once confirmed, attach and adjust back drive linkage.
I have a similar issue.My trans will go into park.If i shift down to low,it won`t go all the way in.it stops at super....It i adjust the cable to go into low.Then it won`t shift fully into park,and the car rolls.I put a new correct length cable for the dual gate.Is there a adjustment i have to do with the shifter itself??Any help.
Well, I'm back! Like previously said, I thought I had it adjusted right for years until one time, the car rolled back in Park! Not right and not good. It sat most of the time in a fairly level garage. So, ever since I've messed with it from time to time since it's been on my two post for a few years. Now, it appears very close to the shift selector spots and will only start in Park and neutral but.....it now rolls again in Park!! When I released the parking brake the other day, it rolled back and the car was making a ratcheting type click under it, which I suppose is the park pawl clicking when it's not catching! I'm a bit frustrated trying to adjust this! Most of my previous 60's/70's cars were manual tranny's and not this finicky! Any ideas. I've been working on a few other minor issues that turned into longer issues to fix. I hope to get this issue taken care of once and for all so I can finish stripping, priming and painting the car this summer. I drove it back & forth on the street a few times the other day and am finally trying to get motivated to finish this up.
How about some simple troubleshooting? If you disconnect the cable from the trans and manually move the selector lever on the trans all the way clockwise to the PARK position, does the driveshaft turn or not? If it does, the problem is the park pawl inside the trans.
Hi Joe, You make a great point. That is the first diagnosis to be done. This issue has haunted me for years. I have the correct OE Dual Gate Cable and all associated parts. I have laid under my car for hours trying to get it set just right. I either get Park or Low. Never both. There are numerous threads on this and they all end the same. No resolution. I even tried shaving parts in the shhifter to get just a little more throw. No deal. It just seems to be a wear issue or something. I have been under other cars and measured and measured. Everything seems the same. I wish we could come up with a difinitive fix/cause for this since there seems to be a few of us out there with the issue. What are your thoughts?
It’s not overly complicated. Assuming the correct length cable is used, the cable span from Park to Low is a finite distance.
The transmission selector span from Park to Low is a finite distance as well.
Use the available adjustments to align the two.
If you can’t get it aligned, one of the components is not correct (worn, incorrect part). Replace with new correct parts as necessary.
If remember correctly, loosen the adjuster then set both the shifter and transmission selector to the neutral position make sure the cable moves freely then tighten the adjuster.
I've been dealing with my youngest granddaughter getting a kidney transplant so I'm just now getting ready to mess with this. I'll try Joe's suggestion first.
I wonder how these cars were consistently set/adjusted on the assembly line? I wish I hadn't effed up the original cable when I first bought it off my brother but, I really don't know if the Park was adjusted correctly then. I bought a numbers correct GM new part when I replaced it.
The car was built in Arlington, TX and was around the Houston area up into the mid 1980's and has an actual 47,700 miles on it. Not sure if wear is the problem since most of it's life was in flat Texas and it's not to hilly there?? But then, I tried the Park setting I thought I had right when the car came down off the 2 post, I had it in park with the parking brake on and I released the parking brake......it rolled backwards pretty fast. The garage floor has maybe a 2 to 3 inch drop to it and that car rolled backwards very quickly! I'll probably never trust the park position anymore on any car. But then, I'm a fanatic about putting the PB especially since I live on a big hill.
All the cars I've restored before were manuals so I've never had adjustment issues with them. I hope to find the sweet spot soon!
I appreciate all the info and comments posted here!
My lever on the tranny doesn't look quite like the one in the Hurst instruction diagram for adjusting the linkage.
Did you ever resolve this discrepancy? If the lever arm between where the cable attaches and the pivot point of the transmission lever is too long, your transmission lever won't rotate far enough for a given distance that the shifter is moved. That would prevent the trans from reaching P or 1 (depending where you adjusted the cable offset). It sounds to me like the cable attach point is too far away from the pivot.
INot sure if wear is the problem since most of it's life was in flat Texas and it's not to hilly there??
When I said wear, I meant the pivot points on the backdrive linkage rods, the shifter cable (inner cable stretch, pivot pint wear), and the shifter ear on the transmission. All of these will wear from years of use, and are independent of the terrain in which the vehicle was operated.
When I said wear, I meant the Parking pawl. And the parts don't appear to be worn and with 47,700 actual miles I wouldn't expect it. The only problem I replaced the cable for was that I got in there and effed the cable up before I knew what the Dual Gate procedure was. My shift lever on the tranny looks like the one in post # 5 and the photo in Joe's post (#8) so the Hurst instruction is most likely a generic representation. I know the car was drag raced around Houston in the 70's and could have been rebuilt since it has a shift kit in it but maybe you don't get that far in to put in a shift kit. I wish, in more ways than one that it was a 4 speed car. It is numbers matching which surprises me. I'm getting back to work on it this weekend....hopefully!
Guys, I appreciate all your input. I know it sounds simple and elementary. If it was just me being stupid or missing something I would accept that. But!, I am not the only one having this issue. Google it or search our forum. Lots of posts about it but no resolution. I know wear is a possibility, my car is an original 44,000 mile car. This issue seems to come up when someone either retro fits their car or changes the cable. Mine is a retro fit but I used all Original NOS parts except the shifter. I will also try to adjust it again. I am quite proficient at it by now. Thanks
Yes, I appreciate all the info and comment. I'm a bit frustrated because I hurked the original cable when I first bought the car off my brother. I put in a new GM cable, and it seemed to work fine but that was in the late 90's or very early 2000's and I was working two full time jobs a lot of that time and it has sat and sat! So, I'm unclear if it would hold in park or not but I suspect it wouldn't! I just can't get over how hard it is to hit the sweet spot with the Dual Gate. That and I have almost zero experience with working on TH350's or TH400's. There had to be a standard procedure to set these things on the assembly line and I'd like to hear from someone who was working on the line....LOL! Yes, there are more than enough threads with questions on the forum. Not very many videos online. I'll keep on it. At least, with a two-post lift, I can mess with it without laying on the floor! Grandpa doesn't like getting up and down and laying on the floor! LOL!
Last edited by OLE442; April 29th, 2023 at 07:30 AM.
Reason: spellin
After a summer of accommodating the care of my granddaughter after surgery & during the summer & school year and working on prep and priming the car for paint( I missed my goal of painting this year) I have the car back up on the two post! I worked yesterday on securing the new stainless transmission lines away for the headers and finishing up mid line brackets! Next up will be setting up the neutral position settings on the Dual Gate and then doing Joe’s suggestion to check it while on the lift!
As I’ve said before, when these cars were built on the assembly line, there had to be a sequence as what to do to set the linkage up properly and quickly since the line just couldn’t stop for a long time while the GM employee effed around with the linkage for every Cutlass with a Dual Gate shifter! There had to be a procedure with a fast way to adjust theses shifters on the line!
I’m hoping to get a few things installed and accomplished while my car is up in the air! Hopefully getting smalls fixed or installed, paint in the spring, sand/buff/ reassembly during summer and interior finished up in the fall it will be done shortly after my 72nd birthday! Like to get a few years of fun and terrorizing the ricers before I stop driving! Lol!
Last edited by OLE442; November 26th, 2023 at 11:20 AM.
You really seem to be missing the point about wear on the linkage parts. 47,700 miles is meaningless if they were racked up on short drives to the grocery store and church (or 1/4 mile at a time as you noted this car was drag raced) where the shifter was moved through the gears more often than what would occur on long highway drives. So get the low mileage out of your head and entertain the idea that some of the linkage components could be worn. I had difficulty adjusting the DG back in the late 1980s when my car was under 20 years old. It took a lot of adjustment to get it so Park and 1st engaged correctly, but it was doable. It just took trial and error with very small adjustments.
June 27th, 2022, 05:56 PM
