727 1st-2nd gear shift point driving me crazy

[rocklaurence]

Hey Guys, I have had this issue from the begining-even after a TransGo shift kit. The trans shifts out of 1st gear too soon and wont shift back down until almost stopped. The TV adjustment is good and I can hold 2nd gear up to 4000 rpm but 1st gear shifts to 2nd at 2000 rpm/20mph and then wont shift down until 5/10mph. Is there a spring or an adjustment in the valve body for this. It really makes the truck work harder when towing and not having it kick down to 1st is frustration when in town.
I looked through my TransGo instructions and on the internet but couldnt find any help.

[shimniok]

Is it just having problems with 1-2 / 2-1? Or is 2-3 / 3-2 a problem?

Only When in D? Or also manually shifting?

Maybe there is a line pressure issue? Or low /aerated fluid?

TV linkage is the first thing to check. Sounds like you did.

[rocklaurence]

Its only the 1-2/2-1 shift points in Auto-drive. Doing a little research and finding that it maybe the Shift Control valve/springs. I replaced all that with the TransGo kit. So, it maybe that the spool valve hole is wallowed out in the valve body. They do have a kit to drill it out and replace with a larger spool. What do you think.

[rocklaurence]

Also, to delay the 1-2 shift [shift at a higher RPM] do I need to go to a heavier or lighter spring?

[candymancan]

Just and FYI my shift points are 1-2 at 10mph and 2-3 at about 20 mph.. and it holds in 3rd gear until i really rev the engine.. Only time i have issues with shifting is if its a quart low from the frigging leak on the shifter seal.

Mine doesnt shift down to 1st gear unless im at like 5mph coming to a stop. It should never drop down to 1st gear when you rev the engine.. Do you know how high the engine rpm's would be in 1st gear if you floor it at speed? Youd blow the engine up. So it sounds pretty normal to me to be holding in 3rd and 2nd gear. And when you rev the engine to full throttle it should only drop to 2nd gear when youre driving at normal speeds never 1st.. Only time you should be in first gear is when your coming to a stop and youre at like 5-10mph.

At least this is my observation


If yours is shifting to 2nd at 20mph then it seems like its holding in 1st gear too long unless your driving on the gas hard from a stop. Shift points honestly will vary on how hard your foot is on the gas.. Drive slow ? 1st to 2nd will be at 10mph 2nd to 3rd at 20mph... Hard on the gas ? 1st will hold longer so will 2nd to third.. Its like this on any vehicle.


Why dont you adjust it on the thottle body/carb ? The line pressure can be adjusted by the T.V cable on the throttle body. Pull it foward to have shift quicker, and give it slack to have it hold gears longer. At least i think thats how it works i forgot which way is which. But i've adjusted TV cables many times, on my ZJ's and so forth and the process is no diff on a carberator

[rocklaurence]

Your vehicle drives like mine --it seems. However, I have another J10 that doesn't have the 1-2 issue amd is better driving. My main issue is that when I slow down for a turn or in traffic to 10 mph it stays in 2nd gear and acceleration is horrible. The other truck drops down to first gear under the same circumstance. Under WOT it shifts at 2000 and 2-3 at 4000 rpm. The 1-2 shift should also be close to 4000 rpm, Shouldn't it?

[candymancan]

Adjust the t.v cable then on the throttle body. Seriously this will fix all your issues and you can get it hold or release gears at whatever point you want...

Do you not kniw!how or where the adjustment is ? If not ill take pics and show you... if you know where it is and how just remember a little foward or back goes a long way

[shimniok]

BTW mine was shifting early for a long time after I adjusted the throttle linkage. I was sure it was right and checked a couple times. But it wasn't. By adjusting a bit shorter, it shifts up and down just perfectly now. I say this because even if you follow the procedure it is worth trying adjusting it a little shorter.

Sent from my XT1096 using Tapatalk

[candymancan]

Well i drove mine today at wot and mine shifts at 3000 rpn into 2nd gear.. not 4k.. even for 3rd gear it never gets to 4k rpm. So i dont think youre right on these 4k rpm shifts.

Why would you want 4k rpm anyway. These engines bog down after 2k rpm.. and actually lose power above that.. im serious lol

[rocklaurence]

During WOT the trans will hold a gear longer--determined by the Governor at the back of the transmission. You can change the springs in the Governor to increase/decrease the WOT shift points. Some street drag cars shift at 6000rpm! But with moderate throttle they still shift at a much lower rpm.
At WOT both shift should be close to the same rpm dictated by the governor. I already have the TransGo springs in the 1-2 shift valve but it dosen't have any effect.