Transmission case sleeves, ZF 4HP22/24 EH valve body questions

[Annddrriy]

Screenshot_20211201-053615.pngScreenshot_20211201-053715.pngHere is a one more diagram of the valve body E-9 version.

[Annddrriy]

What is oil pressure in torque converter when selector gear on D at idle ?

[whiskychaser]

Page 240-5 of Bentleys states mains pressure at idle in D is 5.5 - 7.7 bar measured at the tapping

[Annddrriy]

My question when forward gear are engaged that is A clutch and also E clutch engaged the fluid pressure goes to those clutches A and E others clutches are remain dry and controls by valve body channels for A and B ?

[whiskychaser]

A is on in 1-4. E is on in 1-3 plus R. B is on in 2,4 and R. Refer to the table on page 26 of the Technicians Guide for full details of which clutches are applied in each gear. If a clutch were applied when it should not be, the trans would be likely to suffer serious damage

[Annddrriy]

What does H J and K sprag mean ?

[Annddrriy]

One guy drill a hole in A clutch drum somewhere to release pressure from clutch packs where he made a hole exactlly ?

[whiskychaser]

A sprag is like a roller bearing but it only allows rotation in one direction.

IIRC, some aftermarket suppliers used to supply a kit which included instructions to modify the A clutch piston. Not something I would consider but you will find more information in this thread from 2011:
https://www.bimmerforums.com/forum/s...n-package-info

[Annddrriy]

A clutch piston in valve body or piston in A clutch drum ? I will send a picture of the shaft what he was doing.
Screenshot_20211207-101918.jpgScreenshot_20211207-101805.jpg

[Annddrriy]

Valve body lower front channel for A clutch piston. What is plastic check balls doing when A and E clutches engaged. Check ball closed the hole in spacer plate or not ?

[Annddrriy]

The BMW writeup is here ZF 4HP22E Valve Body Rebuild he using short spring #38 from A damper piston for C clutch damper piston inner spring long #55 is that will work ok ? In manual opposite # 38 to A clutch and #55 to C clutch.

[Annddrriy]

A is on in 1-4. E is on in 1-3 plus R. B is on in 2,4 and R. Refer to the table on page 26 of the Technicians Guide for full details of which clutches are applied in each gear. If a clutch were applied when it should not be, the trans would be likely to suffer serious damage

drive clutch, A; B; E, brake clutch, C; D; F ?

[shogun]

all explained here, see from section 1.1 http://www.jaguarclub.sk/service/pow...n%20-%20zf.pdf
1.1.3 shows in detail operation of gear train clutches, also see 2.1.3 from page 41
2.2 shows a diagram components engagement, hydraulic circuit diagram and which clutch is engaged in which selector position
Transmission Fundamentals http://e38.org/transfund1.pdf

[Annddrriy]

I saw your post about pressure solenoid housing modulation valve spring 5mm is short and I have 5mm long.

[shogun]

the ZF4HP22 repair manual shows in section 1.2 power flow schedule, which clutch is engaged when in which gear, page 11 shows fault finding table, also there is shows a lot of info, maybe that helps https://www.scribd.com/doc/254865544...-Repair-Manual

[Annddrriy]

When selector gear on D than ABC2 and F clutches are engaged. When manual valve shifts to reverse then D clutch is engaged.

[shogun]

this shows the power flow schedule for all gears https://html.scribdassets.com/513gb4...a34134fe7c.jpg refer to 3rd gear and 4th gear description.

ZF 4HP-22/24, DIAGNOSTIC INFORMATION, 3rd Version, "E-9", 4 Solenoid, MODEL "E9", "4 SOLENOID" VALVE BODY, Refer to Figure 36 for identification, location + function of the 5 solenoids, along with the shift solenoid firing order for the "E9" 4 solenoid models
study figures 36,37, 38, http://www.bmwe34.net/E34main/Troubl...ch%20Guide.pdf

[Annddrriy]

Where fluid coming from which valve body channel when A and E clutch apply.

[whiskychaser]

Refer to Shogun's link above or page 26 of the Tech Guide as I mentioned above - 1st gear with the selector lever in first and 1st gear with the selector in D are different. Factory manuals do not normally show which VB channel ATF travels through in which gear. Would be interested to learn if you have found one which does.

[Annddrriy]

seems to be fluid coming from 1-2 shifting valve channel than goes through channel plate and coming from solenoids side and flow to transmission case holes for clutches A and E which is E hole on back side of the case and A hole is in front of the case.

[Annddrriy]

A clutch damper piston is in lover front casting and E clutch damper piston is in lover rear casting its not far for the fluid to travel through a channel plate than to case. is damper piston for returning fluid to that channel and open another channel for brake drum D ?

[Annddrriy]

Screenshot_20211105-053009.pngScreenshot_20211104-042938.pngA and E clutches engaged at 1st gear you can look at this diagram of zf4hp22H model only which is chanell plate different of EH model and don't know about if transmission case are different. As I understood E clutch always engaged to drive output shaft except F clutch when 4th gear on.

[Annddrriy]

I am going to add one more spring to lower front valve body pressure regulator valve to make it no engagement to clutches ABC2 and F and vehicle will at idle stand still till gas pressed then ATF pressure will increase on as we know pressure at idle is 5.5-7.7 bar one's gas pressed then pressure will increase a bit and move the regulator valve than car start to move forward. I don't want car moving forward when selector D is on that means clutch begins to slip at traffic lights or whenever car stop when shift range switch is in position D. Some cars of my friend not moving forward when brake pedal released.
What do you think guys it is going to work or not ? One mechanic said it's going to slip but he is not sure.

[shogun]

probably no one tried it before, maybe you are the first one to make this modification, so trial and error....

[whiskychaser]

Have you considered lubrication if there is no pressure? Also, if the forward clutch is not holding, aren't you are going to roll back when starting on a hill?