Dozer is a 1996 D8R serial number 7XM00754 Does anyone know how to make sure the cooler is working correctly? Experiencing elevated trans temp and trans oil seems to have foam in it. I'm going to pressure test the trans and torque converter and would like to test the cooler as well Thank you for any help
Foam in the oil suggests the possibility of sucking air somewhere between the transmission case (effectively the power train oil pan) and the transmission pump inlet port. Check the condition of the suction hoses/clamps/O-Rings, or whatever seals the lines. Are you using TO-4 specification oil..? Test cooler efficiency by first getting the tractor up to normal operating temp range for both engine coolant and power train oil. Stall the transmission in 3rd speed. As the power train oil temp is rising towards whatever temp sets the high temp alarm off, measure the temperature difference between the oil inlet & oil outlet ports of the transmission cooler and post the results.
Yes I use cat oil. I got the engine and power train up to temp and then stalled in third for about 15 seconds. This made the power train temp go up to 240ish on the gauge. When using a laser thermo, the inlet was 100 degrees and the outlet was 90 degrees. I did not have material to push, the next time I do and it heats up to where I lose power I will do this again. To confirm, the trans cooler is the smaller radiator correct? I also tested: *Torque converter inlet pressure (140psi at high idle) *Low pressure torque converter charging pump (150psi at high idle) *Trans oil pump (510psi at low and 560psi at high idle) *Converter outlet pressure is supposed to be 60psi but I don't have a huge small enough to register 60psi So depending on what you say about the cooler temps it seems the dozer passed all tests except the converter outlet pressure which can't be confirmed as of now Again the issue is after a few hours of pushing the trans temp raises and there is severe loss of power. Trans oil level is slightly high
I would suggest to address the possible suction air leak issues first by checking all the suction hose(s) and at the same time fitting new O-Rings to all of them. The cost of the O-Rings might be $10. If the TC Out temp gauge was registering close to 240 DegF then how could your power train cooler be registering 90/100..? The oil arriving at the cooler should be at the very least in a similar range as TC out, maybe around 200 or even more. I agree with what you suggest and do the same test again when you have material to push and see what that throws up. On the face of it a 10 degree drop across the cooler would be in the ball park, but a lot also depends on the engine coolant temperature. Another test you can do is to stall the transmission as before and run the TC Out temp up until the alarm goes off. It won't hurt the machine. When the temp alarm sounds, shift to neutral and keep the engine at High Idle. Watch how fast the TC Out temp gauge falls, within seconds it should drop like a stone to maybe 10-20 degrees above the engine coolant temperature.
Power train oil cooler is the vertical one in the illustration below.
I will redo the temp test with the proper cooler. I got the machine up to around 150 degrees but it didn't want to go higher without a load. During stall it would quickly go to 250 then once I switch to neutral and idle down it would drop to around 150 again. I did only spend about 10-15 minutes warming it up. Maybe I need longer or need to move some dirt. I will keep in touch
The vertical one above image A A and below 28 correct?
To get the system fully heat-soaked from cold will require at least 1 hour, probably as much as 2. Correct.
Also, I think some hoses may need to be replaced. After I recently replaced the implementation pump I noticed yesterday a hose on top of the trans pump is wet at the connection as well as the hoses below the trans pump are a bit soaked. I did use all new o-rings. Are you blew to confirm which hose is the inlet?
Had 2 different Cat techs come from two different counties. Both did not hook up to anything or do anything except check the filter. There is some clutch material in there. They say replace clutches. Told that to cat technical who said warm it up, then high rev stall in second gear and look if the drive shaft stops. If it stops then it's probably not clutches. I did so and the shaft stopped. Called technical back and he seemed confused and said yeah I agree it's clutches.. so little confusion there. Guess a clutch job is needed. Asked Cat how much to rebuild trans.. they gave prove and said they won't warranty it unless they also rebuild the entire powertrain. So I'll be looking for other options. $25k on unwarrantied labor sounds crappy. I'm going to try to find a reputable place to rebuild the clutches.
I'm going to get the maintenance book and see if it's as easy as a final drive (everything just fits together) or if I'll need torque specs or more in depth stuff. Anyone have experience with rebuilding the trans? Does it all fit together just like a final drive? No torque specs or special something
Before you go tearing a transmission apart that might not need it, answer one question. Does the drive shaft stop spinning when you select ANY gear either forward or reverse.? You don’t have to have the engine at 100% of High Idle to do the tests. So that is 6 tests in total you have to make. Watch the shaft carefully regarding how quickly it goes from full speed to a dead stop.
First gear same result forward and reverse: low idle shaft slows but keeps spinning and doesn't stop. High rev it keeps going fast. Tracks do not move or even feel like it wants to. Second gear same result forward and reverse high or low idle: stops immediately, tracks do not.
It appears from those tests as though first speed #5 clutch has failed, although I note you did not make the tests in 3rd speed, only first & second. The slipping clutch is most likely where the addittional heat was coming from that was causing transmission cooling issues. Looks like transmission out time.
Those clutches are controlled by solenoid valves that can be a problem. You should pull rear trans cover and test #5 clutch pressure. You can swap modulating valve from 3rd speed to see if that helps.
Hang on a sec. This is a 7XM-prefix tractor. Don't they have manually-controlled speed and direction spools in the control valve..? See below. I'd be tempted to drain the powertrain oil and pull the suction screens. There are two of them - see attachment. If the #5 clutch has failed there ought to be a load of burned debris in the screens.
Sorry I didn’t run the serial number. Thought it was a newer 8r with modulation valves.
I must admit when you posted that I had to look just to make sure.....!! Next step. Remove screens and inspect for burned clutch friction material.
I did the test again. First gear forward keeps spinning First gear reverse stops quicky Second gear forward stops quickly Second gear reverse stops quickly Third gear forward stops quickly Third gear reverse stops quickly I will check screens when I drain and collect oil for sos samples. In the past, the rear screen had lots of clutch material (almost like small black rubber thin branches) and metal flakes. The screen by the torque converter is missing from what I was told but I think the tech lied and never even checked. We shall see right? Speaking of.. dunno if any remember me saying the San Diego and Riverside cat dealers are messing with me and constantly try to charge more than they should. Well I got a quote for rebuilding the trans from them and not only is it expensive but they say they won't warranty it unless I allow them to rebuild my entire powertrain, torque, pumps.. I men everything. So I called two different states.. one on the east coast and one in the mountains.. I told them my issues and didn't leave anything out. Not only are they several thousand more affordable but they give a 3 year warranty (1 year 100% covered, 2 years 60% and 3 years 30%) vs no warranty here. I'll be making a road trip soon. California has some issues but they get away with it. This time I asked the tech to do a sample and check screens but he forgot his stuff for that so I'll do it soon. This job is almost over so I'll do it in the next week or two.
So the shaft stops spinning in every speed EXCEPT 1st forward. I don't know what anybody else thinks but to me this is weird for either of the following reasons: - 1. If the clutch for 1st speed had failed the shaft would keep spinning in BOTH 1st speed forward and 1st speed reverse because the same clutch is used for 1st speed in both directions. 2. If the clutch for forward direction had failed the shaft would keep spinning in all forward speeds, i.e. 1st, 2nd, and 3rd. I would still go looking at all THREE suction screens. See attachment. Post photos of whatever you find.
Got the coolant sample back. I asked for a level 2 but it looks like they did a level 1 again. I'll contact them Monday to see if a level 2 can be done. Says trace amounts of non metallic stuff in coolant. Nige you mentioned it is weird that only in 1st forward it keeps spinning but not reverse. That is unrelated to the trans cooler or coolant correct? I'm waiting on samples for all other fluids before checking screens and pulling everything out. Again the last trans oil change the rear screen was full of clutch and metallic flakes
I would say that the problem with the gears is unrelated to the transmission cooler or coolant issues. Based on that coolant analysis I would say that the cooling system needs a good flush with clean water then a refill with some good-quality Extended Life 50/50 Premixed coolant that meets Cat EC-1 Coolant specification. Let me see if I can explain the issue of the "spinning shaft". The transmission has five clutches in total. They are:- a) Two Direction clutches - one for Forward, one for Reverse b) Three Speed clutches - one for First Speed, one for Second speed, & one for Third Speed To engage any specific gear in the transmission, TWO clutches have to engage. They are 1 x Direction Clutch and 1 x Speed Clutch. So for example to engage 1st speed Forward would require the Forward Direction clutch and the 1st Speed clutch to be engaged. To engage 3rd speed Reverse would require the Reverse Direction clutch and the 3rd Speed clutch to be engaged. You get the idea..? So here's where I can't understand what's going on. If the 1st Speed clutch was bad the shaft should spin in BOTH 1st Speed Forward AND 1st Speed Reverse. If the Forward Direction clutch was bad the shaft should spin in all three forward gears, not just 1st Speed. Do you understand my confusion now..? This is why accurate reporting of what exactly happens when you do a particular test is so important.
Yes I understand. I tried the test two different times with the same result. I'll post more sos samples and update on screen asap
Time to take the trans out. It seems like I have to take the finals off and remove the axles. But I see a part about twisting the planetary gears in and I don't have to remove the final but then I can't remove the axle! Do you know if I need to remove the final and axles? I'm also a little confused where I insert the tool to twist 180 degrees to release the planetary gears. Are you able to explain where it is? Thanks
NOTES: 1. The final drives do NOT have to be removed. 2. If the tractor is equipped with a ripper then either the ripper shank needs to be removed, or park the machine on some soft ground and dig it all the way in until the ripper frame is touching the ground. (You will need the ripper frame as low as possible to create the space necessary to remove the transmission.) The procedure is as follows: - 1. Remove the two outer axles and the inner axle by removing the small covers on the outer ends of the final drives. 2. Remove the sliding carrier from the bevel gear shaft. This is done by installing the 1U-7432 Adapter on the the end of the FT-1952 Axle Removal Tool and sliding the assembly into the LH final drive down the axle shaft tunnel a set distance (approx. 37") and then rotating the tool a half turn. Once the sliding carrier is off the shaft the tool is rotated a half turn in the opposite direction and pulled back out again. 3. The transmission & bevel gear assembly is then removed out of the rear end of the chassis. The following Special Tools are essential to remove the transmission. The good news is that two of the three can be fabricated. FT-1952 Axle Removal Tool FT-1897 Adapter (I have a sketch of this one) 1U-7432 Adapter
Thank you this helps a lot! Once I remove the outer axles I will be able to see the inner? Do I push a rod in from one side and inner axle slides out the other side? I'm falling to locate those tools now. Thank you for the ripper advice, I was about to yank it off!! And lastly, is there a visual sign that I fully rotated the carrier group? Honestly I'm not sure what the carrier group is but when I see it I'll probably be like ooo..
Just spoke with CAT, the said they don't carry the tool, I need to build it myself. Any info you have on making the tool is greatly appreciated, including the sketch. Thanks again!
The FT1952 axle removal tool is crucial here. It has a screw thread on one end that engages with a thread on the end of the axle shaft. Basically you screw it on the end of the outer shafts, wiggle & pull and out they come. The inner shaft is a bit more tricky. You use th esame tool but you are fishing for the screw thread on the end of the shaft. Once you find it you screw the tool on & wiggle/pull as before. Hopefully out she comes. I can't believe your Cat dealer does not have an FT1952 tool..!! *** do they use to get axle shafts out on anything from a high-drive D7 upwards..? Because it is an FT (Fabricated Tool) then they ought to be able to help you with a drawing of one so that you could fabricate it yourself, or have someone fab one for you. NOTE: For inner shaft removal I would suggest that the tool be fabricated as close to the factory design as possible. It helps when sliding the tool way inside the tube in the finals where the axle runs to engage the screw thread.
No. The tool goes all the way in from the LH side of the machine and engages on a screw thread on the LH end of the inner axle. The axle does NOT have a thread on the RH side.
I came across a Service Magazine that explains it better than the D&A Procedure. Bascially you use the 1U-7432 on the end of the FT-1952 in order to "hook" behind the planetary carrier and slide it outwards until it disengages from the transmission. So basically you slide the tool in, turn it a half turn, then pull. Once the carrier won't move outwards any more you turn the tool another half turn to disengage it, then slide it out of the hole. When you come to reinstall the axles after reinstalling the transmission, the FT-1952 is installed on the inner axle and the process of installing that axle pushes the planetary carrier back into its correct location. If you have any doubt at all regarding whether the ripper frame will go down low enough with the shank installed i would recommend to remove the shank. But the ripper frame, cylinders, & carriage can stay on the machine.
Telling you these dealers in CA are a joke and have very bad service. Trying to call them back but they're sending to voicemail.
Sounds good thanks again, is the outer right axle removed from the right side or left side like the other two?
Sequence is as follows: - The LH side outer axle comes out from the LH side of the machine, followed by the inner axle from the same side. The RH side outer axle comes out from the RH side of the machine. As soon as you get the small covers off the outside of the final drives (make sure you drain the oil first) you will see the thread on the end of the axle. This is what the tool screws into.
Good thread to read on a Sunday morning infront of the fire Some great information here. On a slightly different note,my D8R would creep forward slightly in 1st gear forward.Only slightly,and at full throttle.I put this down to the brakes been worn abit as the break gets abit of use when jacking the ripper shank into the ground when ripping the high wall down.I like to keep it held back while the shank sinks into the ground under low idle. It never caused any issues with temp etc and it’s new owner reakons it’s been a deceant tractor in the 3 years since I sold it. It was a diff steer unit. I treat my current D8T and D9T the same way.I’ve never stalled them out in 1st F to be honest. Should they stay locked up? I allways thought it was a sign of clutch pack wear?
Can you recommend an oil brand/type for trans and hydraulic? Cat is $100 a pail vs lots of brands online 30-50. I don't want cheap oil, just the most inexpensive good oil! I think you mentioned before hydraulic is 10w and trans is 30w?
From personal experience I would use any of the following brands. I’d stay well away from parts house brands or whatever else they sell. SAE 10W for hydraulic system. Mobiltrans HD10W, Conoco Powerdrive 10W, Shell Spirax S4 CX 10W. SAE 30 for transmission. Mobiltrans HD30, Conoco Powerdrive 30, Shell Spirax S4 CX 30.
Just saw Komatsu has TO30 for 55 a drum and 10w hydraulic for 45 a drum. Should be good right? Cat said TO30 is good.
No idea. Never used it so I have no idea what specs it meets. You asked me for a recommendation and I gave you not one but three......
Yes thank you for that! I'm checking them out now.