Who has an idea ? Th700 no downshift 2-1

[Ralph the german]

Hi guys,

installed a rebuild heavy duty monstertrans th700 on my K5 at april, but not very happy of the characteristics. Had two month of expirience to set the TV.
Yesterday I installed a new TV and set it alike instructions of bowtie trans web page. Upshifts are right and also downshifts without a light clunk like before are ok, kickdown at wot also. But, from first installation day, if I start cold on D or circle D, truck starts with first gear, at the next stopping at traffic lights, the truck starts with second gear on green light. If I shift at stopping to N and back to (D)/D, truck starts right in first. Now my question is, were can I search. Is it a governor problem, or is it a 1-2 valve problem. I have no idea of the function inside and the ATSG book gives me no answer. I mailed to monstertrans tech support and wait for answer, but warranty over the big water is hard to handle. For any ideas I would be very thankful and lucky.

 

[Fordum]

I'm sure someone with more experience than me with that tranny will help more, but if it started it as soon as you installed the TV cable, I would double check that adjustment and installation.
As I am sure you have read, that adjustment is critical for the life of that tranny.

Read the setting instructions again, and readjust it. Make sure that there is no slack in it when the throttle is closed.
And it should bottom out just as the throttle reaches its limit.
It has to move as soon as the throttle does to increase the pressure on the clutches to get ready for the load that is coming.

You might have the wrong length cable for that truck and throttle linkage.
And, I have read about having to change the mounting point if you go with a different carb, so the mounting geometry is critical also.

Also, double check the shifter linkage. Make sure its not close to 2 when in D.

 

[Ralph the german]

Hi Fordum,

my expirience with the TV was a cause of hard up and downshifts and I take a new TV (right for the 5.7 TBI) with a new ratching/clamp. The downshift problem began from first day, I thought ,now I have a new trans but was not happy about it in order to the OEM. Now I know why, it starts in second and so I feel, there are only half of the horsepowers at the first meters. Yes I know about critical adjustment for the life of the trans, I read this up and down the web, so I always drive low miles from home until I be sure of that tranny.

 

[Blue85]

I can't think of anything you could do with the TV cable that would cause this issue. Anywhere from idle to WOT should put the trans in 1st gear. I have 3 guesses:

1) The governor is sticking
2) The 2-1 shift valve is sticking or leaking
3) The servo is sticking, keeping the band applied

The builder should be able to walk you through the troubleshooting, so that you fix it yourself or need to ship only the valve body. Since you have a warranty, it may be best to wait and take stuff apart only by their direction.

 

[Ralph the german]

Hi Blue85,
thanks for your help. This three points are also my idea so I have a wait for what monstertrans gives me an answer. Settings on the TV are ok, I don´t also think there is a fault setting, cause there is no TV work when I stop in traffic with closed throttle, other parts like you guess do the work to downshift the first.

 

[Ralph the german]

so guys, taking on the old thread. The fault problem was a sticking governor, I took my old in and the problem has gone. Monstertrans send me another gov what arrived today ! But, it`s a used part also. From yesterday new problems from the rebuild monstertransmission. The trans does no downshifts and stopping on traffic, the trans shut my engine down. If I start new and shift in gears, downshut the engine also. Same procedure one hour ago, stop on traffic, engine down. Shift on R it make a clonk from downstairs and on next step shifting, the motor and trans is well in idle with gear shiftet. Monstertrans now send me new overhaul kit with shift kit and beast sunshell. I don`t know what new fault is with this f*** trans. I do not recommend this shop, never buy at monstertransmission. Other guys also have problems like this and talk, the shop sells rebuilds with junk and worn out parts.

 

[Blue85]

So you replaced the governor with another one you had laying around and the problem was solved? Then without any more changes a new problem started?

If the trans is stalling the engine, maybe the torque converter clutch is not unlocking? Either that or you have real broken parts. This must be what the vendor suspects if they shipped you a sunshell.

Do these guys dyno test the transmissions before shipping? I think I would insist on this before buying a unit overseas.

 

[Greg Ducato]

I agree with Blue in that it sounds like the torque converter clutch is staying applied when you come down to a stop. This could be a sticking valve or solenoid. From what you describe with a governor problem, and now this converter problem, I think you will find that something is generating quite a bit of debris in the trans. I hope they are sending you a new converter as well as that could be the source of your debris, and if it isn't , it will be as contaminated as the rest of the trans and impossible to clean out without cutting it open. Not sure why they sent you a new sun shell unless that is a consolation prize?

 

[Ralph the german]

So you replaced the governor with another one you had laying around and the problem was solved? Then without any more changes a new problem started?

yes, between the 2 problems a half year is gone

If the trans is stalling the engine, maybe the torque converter clutch is not unlocking? Either that or you have real broken parts. This must be what the vendor suspects if they shipped you a sunshell.

can it be the solenoid ? the converter is also a new. I asked a beast shell, cause in theirs heavy duty isn`t it. Today got their tech reply an told me something like low line pressure and the sprag can break....

Do these guys dyno test the transmissions before shipping? I think I would insist on this before buying a unit overseas.

on their site they tell about dyno each, but overseas I only can take their words....

I agree with Blue in that it sounds like the torque converter clutch is staying applied when you come down to a stop. This could be a sticking valve or solenoid. From what you describe with a governor problem, and now this converter problem, I think you will find that something is generating quite a bit of debris in the trans. I hope they are sending you a new converter as well as that could be the source of your debris, and if it isn't , it will be as contaminated as the rest of the trans and impossible to clean out without cutting it open. Not sure why they sent you a new sun shell unless that is a consolation prize?

When I drive in second gear until the engine is warm enough and this problem
seams like ok, could it be a fault with the lock up solenoid or valve ? Cause lock up only works in 3 and 4 ? If it`s so, I can first drain it, install new solenoid, filter and controll the valve.
Monstertransmission does send me a "deluxe rebuild kit, new shift kit and beast shell" first as warranty exchange.

 

[imiceman44]

Does reverse work?
If it does then you might havea problem with the Torque converter, or the solenoid that controls it, but if you don't have reverse but instead goes forward, the the forward clutch is stuck.
Had that happen to me in one tranny.
Good luck finding out what it is.

yes, between the 2 problems a half year is gone

If the trans is stalling the engine, maybe the torque converter clutch is not unlocking? Either that or you have real broken parts. This must be what the vendor suspects if they shipped you a sunshell.

can it be the solenoid ? the converter is also a new. I asked a beast shell, cause in theirs heavy duty isn`t it. Today got their tech reply an told me something like low line pressure and the sprag can break....



on their site they tell about dyno each, but overseas I only can take their words....



When I drive in second gear until the engine is warm enough and this problem
seams like ok, could it be a fault with the lock up solenoid or valve ? Cause lock up only works in 3 and 4 ? If it`s so, I can first drain it, install new solenoid, filter and controll the valve.
Monstertransmission does send me a "deluxe rebuild kit, new shift kit and beast shell" first as warranty exchange.

 

[Greg Ducato]

Is your lock-up converter controlled by voltage to the solenoid or is it controlled hydraulically from inside the trans without an external voltage source? If it is electronic, simply unplug the voltage and test to see if the converter clutch still tries to apply.

 

[Ralph the german]

Does reverse work?
If it does then you might havea problem with the Torque converter, or the solenoid that controls it, but if you don't have reverse but instead goes forward, the the forward clutch is stuck.
Had that happen to me in one tranny.
Good luck finding out what it is.

yes, reverse is working. When the problem happens last time, the trans stalls the engine, I restart the engine and shift to reverse. At this moment, it make a clunk noise from under the truck and the trans don`t stall the engine and I can drive on. Sometimes before the stall problem was there, this noise happens also afew times.

 

[Ralph the german]

Is your lock-up converter controlled by voltage to the solenoid or is it controlled hydraulically from inside the trans without an external voltage source? If it is electronic, simply unplug the voltage and test to see if the converter clutch still tries to apply.

yes, that is an idea. This th700 has a connector on driver side for the lock up solenoid I think. So, I can drive in third, not use the second always as write before, and test if there is a converter clutch apply problem to the trans.

 

[Ralph the german]

So guys, news from germany. Today I disconnected the wires from the trans terminal and drove about 40 km without the overdrive. The trans shifts well all 4 gears and didn`t stall the engine down. No noise apeard. And what wonderfull, there is a soft downshift 2-1 that I never had before. What had I to do on the trans next ? Change the solenoids and test the valves behind them ?

 

[Greg Ducato]

Ralph, you have eliminated the lock-up feature of the torque converter by disconnecting the voltage. You will still have overdrive without the converter clutch, so your trans will still function as a 4 speed with 4th being overdrive. First thing I would replace is the TCC solenoid that bolts into the front of the case and goes into the pump. While it is removed, you can use a scribe to stroke the valve behind it and make sure it is not sticking. There will be a small hole in the retainer that you can use to push your scribe through to stroke the valve. Total stroke is less than an inch and the valve should return on its own once you release it since there are springs behind it. Also, check to see if your brake switch is canceling voltage to the trans when you apply the brakes. Let us know how you make out.

 

[Ralph the german]

to understand it right Greg ; I have 1-2-3 gear, 3 lockup, 4 is overdrive, 4 lockup ?

 

[imiceman44]

to understand it right Greg ; I have 1-2-3 gear, 3 lockup, 4 is overdrive, 4 lockup ?

Normally your 700R4 would be 1,2,3, 3 lockup, 4, 4 lockup.
Now with the wires disconnected you have 1,2,3,4
That means you have figured out the problem is in your lockup.
The procedures that Greg told you to do, will let you know what is causing that problem.
The brake pedal switch should disconnect the lockup, if it's not that could be one.
The valve not returning ( the one he said to test with a scribe) also does that.
In the meantime you can drive it now and you just will be using a little more gas and possibly get more heat in the tranny because you don't have lockup, until you find what is causing it to get stuck.
Good luck.

 

[Greg Ducato]

Normally your 700R4 would be 1,2,3, 3 lockup, 4, 4 lockup.
Now with the wires disconnected you have 1,2,3,4
That means you have figured out the problem is in your lockup.
The procedures that Greg told you to do, will let you know what is causing that problem.
The brake pedal switch should disconnect the lockup, if it's not that could be one.
The valve not returning ( the one he said to test with a scribe) also does that.
In the meantime you can drive it now and you just will be using a little more gas and possibly get more heat in the tranny because you don't have lockup, until you find what is causing it to get stuck.
Good luck.

What he said

 

[Ralph the german]

yes,thanks, so I guess too. 4 is overdrive, cause it`s 0.7 geared. (like manuals in 5/6).
I order the brake switch, solenoid, filter and so on and open the tranny.
Funny, this answer I got today from monstertransmission, so I think their techs have no plan of what they do ;............> Soft downshift usually means there is not enough line pressure. No OD could be the servo assembly not getting enough fluid
> Melissa Hooven
> Monster Transmission & Performance
> Tel: 800-708-0087
> Fax: 877-275-1615

 

[Greg Ducato]

yes,thanks, so I guess too. 4 is overdrive, cause it`s 0.7 geared. (like manuals in 5/6).
I order the brake switch, solenoid, filter and so on and open the tranny.
Funny, this answer I got today from monstertransmission, so I think their techs have no plan of what they do ;............> Soft downshift usually means there is not enough line pressure. No OD could be the servo assembly not getting enough fluid
> Melissa Hooven
> Monster Transmission & Performance
> Tel: 800-708-0087
> Fax: 877-275-1615

Not sure I understand where those tech answers came from