ZF Transmission Problems

HATCHEQUIP said:

Answers to SOME of the questions here
1st case problem: Just had one come thru the shop no 1st or 2nd just 3rd and 4th sound stupid that they let you have the high gears but not the low ones but your problem is that wire #i think it was 25 and letter has no power the power goes thru the parking brake switch and thru the declutch switch and the declutch pedal and thru the 2 brake preasure switches then to the computer behind the seat. We found the problem to be low brake preasure not letting current thru the preasure switches.blown oring on the spool in the brake accumalator valve and 1 accumalator that was not holding preasure.

2nd samsung problem: We had a jcb come thru with sometime no direction control in forward and found it to be a micro switch in the controler. On some units that have a rubber boot you can pull it back and listen for a click when tou shift it back and forth maybe spray a little contact cleaner in there to get to working or pull controler off and drill out 2 rivets and you can get to the switches to replace or just give them a good cleaning and then force a little dielectric grease past the plunger into the guts of the switch and use screws or rivets to put back together. The shifter only comes as a complete assembly and is pretty pricey. Hope this helps some one as im getting cramps from all this typing. Havent done this much since highschool alooong time ago. Yall take care.

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The break on the first axle is holding all the time and will that come back to accumilater number 1 and where is it?

Ive slept, but sitting in seat right side under cab maybe back a little, I think inside frame, valves and accumulator wiring and brake lines hook to them, be sure that pedal isn't staying part of the way depressed because dirt under the back of it holding it from coming all the way back up, hope this helps

im looking to buy a Samsung loader sl150-2 with a zf transmission when I first start it, I have to wait 5-10 min for it to warm up before it will move, the engine starts and runs fine but is wont move. is this normal. it is a good looking machine with no known problems. the transmission just worries me did you fix your machine or do you have any suggestions

Just been reading this thread and others.

I have a Case 621B XT with no forward or reverse.
FNR checks all ok
Bypassed the transmission relay to ensure power onto pin 22 on ECU
Checked grounds at fuse panel and also ensured ECU chassis is grounded

Power up the loader and I get one click, pause, then 3 clicks (1----111) - so I believe I have a short

Checked pins 14, 15,31,32, 33 in different fnr positions as per the manual and I get no power.

Checked resistance to all solenoids and I get exactly 87.3 ohms for EVERY solenoid (weird - expected some variance)
I removed the ECU connection and tested solenoids via harness connection and get same readings, BUT I also noted the ground pin 34 is measuring impedance to ground.

Looking at the schematic, these solenoids have a direct wire to ECU pin 34 ground, and if this is disconnected - there should be no impedance (open)

My question to the gurus - Is this a short the computer senses and hence shuts off???

I am thinking to open up the solenoid cover and check each wire, but damn awkward area to work (any info would be of great assistance)

(BTW -I am assuming my ECU is good, but note this is a restoration project - unit has not been driven for 5 years - apparently all worked before parked down)

cheers

O

Brake Accumulators

spanner said:

Hatchequip. I had exactly the same issues. 621B no 1st or 2nd. After much poking around phoned Case dealer who said check brake accumulator pressure. Sure enough one circuit was low. Accumulator control valve is behind a plastic plug just at back of the right rear wheel. Tried adjusting but made no difference . Replaced valve and instantly fixed the problem. Apparently this is their idea of a brake failure sfety control. No 1st or second renders the machine almost useless but still moveable. This machine also had erratic selection of fwd /rev. Swapped out controller with a sister machine and away it went. I didn't try to fix it though just got a new one.
Just on that accumulator control valve, don't try and adjust it without gauges and numbers.

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Spanner can you please indicate where to locate the brake accumulators? I have an 821 I am working on and only found the one main accumulator under the driver seat area. Also did the machine totally lock up when in first and second?

thanks

I have a is a kawaski 65Z wheel loader,the hydrauic line under the seat sprung a leak had to take seat off and fix got it fixed hooked back in,its the line on the pump on transmittion. Everything worked great before now it wont go forward or reverse everything else works any help would be great

hi all, ive got a samsung 120-2 that will not engage either F or R in any gear it will only flash D5 which im assuming is a code. the loader just had a reman engine put in by another shop and customer test drove it, loaded it on the trailer and backed it off at their shop, shortly after they tried to run it and nothing. ive gone through the shifter and its all showing power, the trans is reading at 233 psi, the speed sensor is fine, and all fuses behind the seat are good. ive searched the web and theres not much for these, any help would be appreciated

I would suggest checking parking brake relays and anything to do with service brakes. Most wheel loaders now have interlocks that prevent transmission operation when there is anything perceived wrong in brakes and steering.

could you tell me the location of the relays? ive pulled all the panels off the outside and a few inside around the steering column, today i will pull the seat and the panel behind it. TIA

I've only looked at these loaders for condition inspections. In many of the loaders I have worked on the relays were behind the seat or in one of the consoles. Usually you can find them by operating a function and listening for the click when they shift. Most machines will have them in a couple of places. Do you have a service manual on the machine?

May be of help

the relays have been found, but im havung trouble locating the declutch relay for testing and the park brake relay. also is this the tcu? it was mounted under the seat and has the wire harness from the gear selector running to it, i would assume that it is but its a bosch unit and the gear selector has zf printed in a few locations.

Bosch bought 50% of ZF their name is now on the TCU's attached is a Lull but the 35pin outputs should be right on the est. TCU

wzntme said:

can someone help me please,,i am working on a case 621b and the transmission will not do anything?

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Will engine start but won't go into gear? Is there any warning lights on? Is brake pressure okay?

So in the end, is there a generalized consensus on whether ZF transmissions are overall good, or are they categorized as problematic? I'm faced with a decision on basically parting out an otherwise serviceable wheel loader (JD 544) over a bad ZF. Or so I've been informed. I have not tested it in any way to confirm that it is bad.


I'll amend this post with a query. I have been told that JD only used ZF transmissions in the 544 series loaders for a couple of years, then reverted to Allison built transmissions. Can anyone confirm that, which if true leads me to question why. Was it a question of design shortcomings, inability to supply the required quantity by ZF, or some other reason?

I don't know much about them but did have some experience with the old Terex artics back in the nineties. As I recall they were TA somethings but could very well be wrong about that. I seem to recall them being 22 or 25 tons. The trucks had Deutz engines and ZF transmissions that had a bad habit of breaking. It was a messy job in that the whole top of the front section had to come off to get to the tranny and ZF would not allow anyone to rebuild them. At any rate we heard later on that Terex went cheap on the box and put one size too small of unit in those trucks. The 30 ton trucks came out a bit later with the Cummins M11 engines and bigger ZF boxes and they worked all right for an Artic. Wheel loaders get slammed hard for a lot of years by people that really shouldn't be on a machine. I've inspected Deeres with over twenty thousand hours on the clock and the owners swear the grinders are original.

Which letter designation 544 are we talking about? 544E and newer were all ZF transmissions and all replacements are ZF. Allison was the transmission used in the 544D and older.

I have seen a lot of the ZF transmissions in many makes. They have proven to me to be very tough to beat with proper maintenance and operation. If they have the proper TCU, they can be recalibrated through their life to last many years. The majority of the issues I have run across have been purely electrical in nature.

mg,
I have two loaders at play at this point. I do not know the year of mfg right offhand, but one is a E and the other a G. The E has a grapple that the owner wants to move to the G (standard bucket), since it has no apparent mechanical problems. Overall, it doesn't seem to be in great shape. Very weathered, rust at the door bottoms and sills, broken glass, blank instrument cluster. I think it's going to take a lot of work to call it a good machine. I started it today. Cranked about one revolution and was running. I was actually going to just bump it to see if the battery was up, and to my surprise, it fired right off. Wasn't cold today, just in the 40's, but I was still surprised.

The G hasn't got a battery on it so I could not just start it to see how it acted. I know it was trailered in. I'm under the impression it was parked for transmission issues. I probably need to verify that before making my recommendation. Overall, it looks like a better cared for machine. The ZF transmission is a 4WG-150 for reference.

I can imagine the headache of moving the grapple, with controls and all from one machine to the other, plus finding out what else the machine will need. I have not checked to see if multiple pumps are on the grapple machine to run it. The G just has the ordinary 2 function stick, which is awfully stiff and will not return to center on its own. Feels very dry, but I have a bad feeling about it. But to make this swap work it would probably go to the other machine anyway. Oh, and under consideration it parting out the E after taking the grapple off.

Vetech63, I haven't worked on that many, but so far, every one has been electrical as a root cause. ZF is as good as any afaik. Well, except for some of their recent sports car products. 9 and 10 speed automatics...has to be tough to pull off.

Here's a couple of shots of the machines. Just overview.

I personally would have the transmission checked out before you make any decisions. In the past getting electrical schematics for the ZF was a chore in itself but a lot has changed over the years with the information available. Make sure whoever checks it out is knowledgeable with these transmissions systems on hydraulic and electrical. It could possibly be a reasonable repair with minimal cost. If it proves to be a major internal issue, I have a great contact with a factory authorized rebuild center. The last time I sent a transmission like this to them, the standard rebuild (less hard parts such as drums, shafts, etc...) was around $5K. That was a teardown, bearing, seal rebuild, and with me shipping the transmission to them. Of course...…..that was around 10 years ago!