My JD 4030 diesel with Quad Range (2x8) does not smoke and the engine runs good. The hydraulics work good....front end loader, Rockshaft and 3 pt. hitch, steering and brakes. There are no hydraulic leaks and oil and hydraulic fluids are ok. It maintains good RPM whether driving, pulling or using the PTO for baling or brush hogging. In other words, the engine does not slow down under load. However, after running and operating for a short while, the tractor starts moving slower...especially while moving up an incline. It will get to a point where, in order to get the tractor on up the incline, I have to go into granny gear. Even after a while when operating on level ground it begins to start creeping. It seems like there is either some kind of slippage within the power train system or the brakes are on. The manual states in diagnosing problems of this nature that slippage in all 4 speed gears could be caused by "Plug leaking or missing from brake housing". I'm not sure where to find the plug is located in the brake housing or even how to get to the brake housing. I would sure appreciate some suggestions on this problem I am having.
JD 4030 - Creeping slo-mo
- Thread starter okrancher
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Tx Jim
New Member
Quad-range trans has a hyd hi-lo. Does tractor slow down in both speeds of this hyd hi-lo? There's 2 possibilities either the traction clutch is slipping or the hi-lo clutches are slipping. I suggest to check clutch pressure on clutch valve on LH side of tractor. Pressure should be 155-165 psi. I have no idea what "plug leaking" you're referring to and I was a JD dealer service manager back in 70's-80's. There was a clamp(parts key 21A) on a line on the hi-lo housing that could break letting line slip out loosing either high or low speed.
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beenthere
Super Star Member
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Jim
21A ?? I don't see it, just sayin...
21A ?? I don't see it, just sayin...
Tx Jim
New Member
Sorry I posted incorrect photo the 1st time.
Hello Tx Jim....Thanks for your reply. The tractor slows down in either High or Low in all four of the range speeds. The traction clutch appears to be ok as I can press the pedal in and let it out and the traction engages. Also I forgot to mention that I have replaced the Hydraulic Filter recently. The "Plug leaking" I mentioned comes right out of the tech manual...I'll attach a copy of the page. It has to do with the underdrive brake housing assembly.
Back to your reply, this problem I am having seems to appear after operating the tractor under load after 45 minutes or so. In order to keep speed constant, or increase it, I have to throttle up and increase the rpm. Usually I operate at 1500 rpm...but as time goes by I will have to increase rpm up to 20,000+ to keep the tractor moving....I don't like exceeding that because on my tractor that is the max rpm I should use for PTO usage. This problem did not just suddenly appear. There have been symptoms showing for some time..but now it has reached the point where I must do something about it and get it repaired.
Where is the Hi-Lo housing you reference? Also, would you please tell me where your page attachment came from? I will put a pressure test on the system tomorrow and let you know what I find. Thank you for your suggestion and comments.
Back to your reply, this problem I am having seems to appear after operating the tractor under load after 45 minutes or so. In order to keep speed constant, or increase it, I have to throttle up and increase the rpm. Usually I operate at 1500 rpm...but as time goes by I will have to increase rpm up to 20,000+ to keep the tractor moving....I don't like exceeding that because on my tractor that is the max rpm I should use for PTO usage. This problem did not just suddenly appear. There have been symptoms showing for some time..but now it has reached the point where I must do something about it and get it repaired.
Where is the Hi-Lo housing you reference? Also, would you please tell me where your page attachment came from? I will put a pressure test on the system tomorrow and let you know what I find. Thank you for your suggestion and comments.
Tx Jim
New Member
Hello Tx Jim,
I have not checked the clutch pressure....am having a pressure line/gauge fabricated to do this at our local hardware store....will get back with you on this after I get a pressure test.
As to your suggestion about checking the hyd filter relief valve seating correctly....is this on the outside of the tractor (left,driver side on the tranny case)? Is this the same as the "pressure regulating Valve plug" indicated in Fig. 4 on the page that I sent you as an attachment?
Thanks Tx Jim. I appreciate very much your time on my problem.
I have not checked the clutch pressure....am having a pressure line/gauge fabricated to do this at our local hardware store....will get back with you on this after I get a pressure test.
As to your suggestion about checking the hyd filter relief valve seating correctly....is this on the outside of the tractor (left,driver side on the tranny case)? Is this the same as the "pressure regulating Valve plug" indicated in Fig. 4 on the page that I sent you as an attachment?
Thanks Tx Jim. I appreciate very much your time on my problem.
Tx Jim
New Member
Hello Tx Jim,
The pressure gauge tested zero, which I find hard to understand/believe....after all, I CAN drive the tractor and shift gears and it operates in all 16 forward speeds and operates in reverse....so something must either be wrong with the gauge or I have plugged into the wrong hole (which I don't think is the case). Anyway, here is something else to consider.. My hydraulic fluid is dirty brown...not black, but sort of coffee brown. I am going to change the fluid and put on a new filter today, and then see what happens.
Also, this hi-lo oil tube you told me about that may be loose ....isn't that located on the Two-speed planetary Assembly/Brake Housing? In order to get to this don't I have to do a separation? If changing the hydraulic fluid/filter doesn't fix my problem, more and more it seems like I am going to have to do a separation. With a Soundguard cab removal this is beginning to look like a major, major repair job.
The pressure gauge tested zero, which I find hard to understand/believe....after all, I CAN drive the tractor and shift gears and it operates in all 16 forward speeds and operates in reverse....so something must either be wrong with the gauge or I have plugged into the wrong hole (which I don't think is the case). Anyway, here is something else to consider.. My hydraulic fluid is dirty brown...not black, but sort of coffee brown. I am going to change the fluid and put on a new filter today, and then see what happens.
Also, this hi-lo oil tube you told me about that may be loose ....isn't that located on the Two-speed planetary Assembly/Brake Housing? In order to get to this don't I have to do a separation? If changing the hydraulic fluid/filter doesn't fix my problem, more and more it seems like I am going to have to do a separation. With a Soundguard cab removal this is beginning to look like a major, major repair job.
Tx Jim
New Member
I heard of checking/replacing hi-lo tube clamp by removing clutch valve housing. SGB(cab) doesn't require removal to split tractor between engine & clutch housing. While trans oil is drained check/clean trans oil sump screen.
