Kubota L4701 150 hours rear end stripped gear popping noise. NOW WITH VIDEO

chim

Well-known member

Equipment
L4240HSTC with FEL, Ford 1210
Jan 19, 2013
1,738
821
113
Near Lancaster, PA, USA
I've looked at this thread without being able to sort things out to any extent. This morning I watched his YouTube video and recognized a sound. My L4240 makes what the OP thinks is grinding gears on his tractor.

This happens when I try to move the tractor in a gear that's too high. Example is going up the "step" into the shed in HI range. Generally the front wheels roll up and over easily, but it takes more effort for the rears to climb in. It also happens when jumping on the hydro pedal in HI attempting to go full speed from a dead stop. This is particularly noticeable at lower RPM's.

I made a video of mine a while back. See below. Notice that the loudest noise was when I let off the hydro pedal. I did a full service on the tractor and after replacing fluids and filters the noise went away except as mentioned above. The old UDT2 was discolored and appeared to have been cooked a bit.

Neil Messick made a video concerning a similar noise but that wasn't with a HST trans. In that video it was a normal hydraulic sound.

 

#40Fan

Active member
Jul 21, 2022
243
139
43
USA
His only made the noise when hitting the brakes.

Yours (chim) sounds like a heat shield rattling around.
 

GrizBota

Well-known member

Equipment
L3830HST/LA724, B2601/LA435/RCK54-32, RCR1872, CDI 66”grapple, pallet forks
Apr 26, 2023
1,098
699
113
Oregon
His only made the noise when hitting the brakes.

Yours (chim) sounds like a heat shield rattling around.
Agreed. I’ve listened to the audio in both the OP’s video and this new one. They do not sound similar to my ears. Nor is it a similar action taken taken to result in the audio heard.
 

fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
6,313
4,003
113
Eastham, Ma
I've looked at this thread without being able to sort things out to any extent. This morning I watched his YouTube video and recognized a sound. My L4240 makes what the OP thinks is grinding gears on his tractor.

This happens when I try to move the tractor in a gear that's too high. Example is going up the "step" into the shed in HI range. Generally the front wheels roll up and over easily, but it takes more effort for the rears to climb in. It also happens when jumping on the hydro pedal in HI attempting to go full speed from a dead stop. This is particularly noticeable at lower RPM's.

I made a video of mine a while back. See below. Notice that the loudest noise was when I let off the hydro pedal. I did a full service on the tractor and after replacing fluids and filters the noise went away except as mentioned above. The old UDT2 was discolored and appeared to have been cooked a bit.

Neil Messick made a video concerning a similar noise but that wasn't with a HST trans. In that video it was a normal hydraulic sound.

That sounds terrible!
 

chim

Well-known member

Equipment
L4240HSTC with FEL, Ford 1210
Jan 19, 2013
1,738
821
113
Near Lancaster, PA, USA
Yes, mine DID sound really awful.

When I listened to the OP's video, I picked up on the sounds the tractor made at 0:14, 1:37 and 2:00. Right or wrong, I thought those were the sounds he was trying to demonstrate based on my interpretation of what he said. The many other times were just squeaky squealy brake sounds that I discounted.

Neil Messick has a short video of a customer''s tractor that makes a similar sound. Although the transmission is different from ours, there are probably some things in common such as fluids being forced around.:


Here's my original post from last year. It's been running fine for 14 months (85 hours) since then:

 

Nicksacco

Well-known member

Equipment
Kubota L35 TLB
Sep 15, 2021
555
298
63
Bahama, NC
Good and useful information for sure.

The part I don't get on the original poster's thread is the weird noise at the beginning of his video - which is NOT the same as when he backs up and hits the brakes. Two different noises. And it sounds as if his rpms are quite above idle.

The weird noise does sound like stripping gears, but is it? Could low tire pressure cause that or is it something loose structurally creaking like creaky floors? It only does it once. Cold hydraulic fluid?

I believe the brake structure of my L35 and his tractor are the same and why his squeaks in reverse has me stumped since both our tractors utilize enclosed wet brakes. How would brakes in lubricant squeak?
Low hydraulic fluid? I would've thought he'd checked that.

You can hear the squeak timed exactly as his foot is on the brake (at first I thought the squeak was in the brake actuating mechanism itself).
Could it NOT be the brake that's squeaking but something moving in the HST when the foot comes off the treadle and the brake is applied?

Oh well, all we have to go on is his video and that's about as good as it gets.
 

Rdrett

Member
Dec 5, 2017
222
6
18
Paris Ky
I wanted to post an update on my tractor, I have had time to use it since the repair.
The brake replacement has fixed the squeaking noise when hitting the brakes and the loud popping noise when hitting the brakes.
‘They must of done something with because the “creep” when releasing the HST pedal and leaving it in the neutral position is a lot better, it creeped 4 times faster before taking it into service compared to now.
The parking brake still won’t hold the tractor back on a hill, it will still roll. The odd part is it sit on a hill for 30 minutes without rolling but all of a sudden it started rolling.
I think the parking brake need’s adjusted, I can push the pedal past all 3 notches on the parking brake.
Does anyone know where I can buy a service manual to get the brakes adjusted properly?
 
  • Like
Reactions: 1 user

NCL4701

Well-known member

Equipment
L4701, T2290, WC68, grapple, BB1572 box scrape, Howes 500, 16kW IMD gen, WG24
Apr 27, 2020
2,488
3,508
113
Central Piedmont, NC
IMG_1155.png
IMG_1157.png

I’d still suggest downloading the WSM Fordtech linked. I have that one and have found it to be quite helpful in addition to the OM.

Glad to hear it finally got fixed.
 
  • Like
Reactions: 1 user