danmckennat

need help with 2009 honda rancher 420

33 posts in this topic

i am running out of options and not sure what to do anymore. i have an 2009 honda rancher 4x4 foot shift model. i have only put about six tanks of gas through it since i bought it. i have developed a really bad grinding noise from the rear end only when you make right hand turns. it does not grind while driving straight or turning left only when you turn sharp to the right. you can hear it and feel it throughout the bike. it has been into three different dealerships now and not one dealership can figure out what is causing the grind. they said the bearing all look ok, the shims are to spec and everything in the rear end looks normal. it has solid rear end with drum brakes. Is this a normal sound for this model ?or does anyone know what is causing this grinding noise?

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have you drained your rear diff oil? if so was there any metal in it? it could either be to low of side bearing preload in the diff or your left rear wheel bearing is brennelling or flaking but has not yet loosened off. i have seen this on alot of bearings. especially ball bearing types. this is more prominent in KLM bearings. I hope this will be of some help.

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I agree, draiin that diff oil to see if there are metal filings in there. Turning sharp right would put weight on the left side of the atv. Does it sound more form the rear or wheel area?

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i didnt get to see the fluid cause the dealership drained it so who knows if they will tell me the truth. could the bearing just be defective from the factor? the sound seems to like it is coming from the rear diff, the sound is on the left side in the rear end and you can feel it in the left foot peg

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yes it is possible to get defective bearings from factory. if you put enough miles on your atv (approx30 miles or so the oil will pick up any metal left in the diff. they will not get all of the filings out when they drained it. i would pick up the factory rear diff oil and drain it yourself. catch it into a clean white container. then shine a flashlight into it. if you see metal reflecting the light in the oil then there is possibly a rear diff issue. if not i would do some close inspecting of the left rear corner. does the noise sound loud and higher pitched or is it deep and hollow sounding?

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its a deep grinding noise, the dealer just told me that they found some scoring on the gear in the transfer case but said they are not doing anthing about it, could that be a cause?

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yes that would cause the noise. if it is a deep noise it is coming from internal parts. if there is scoring on the gears in the transfer case then i would question it. is it still under warranty? if it is i would say WTF!!! there should be no scoring on your gears unless there is a problem. if it is under warranty i would be very stubborn and make them fix it. sometimes you have to email the factory complaint department.

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got it back from dealer they tried a fatter shim in rear end and that helped a little but still there, honda said there is nothing more they can do so i am on my own, i think the next step is to try new bearings cause my mechanic at work said there is no way to check sealed bearings and they could look ok to the eye but really there could be a small defect with them so monday i guess will order some new ones and hope that is the problem

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Is this machine still under warranty? If so, I would not let the dealer tell you that there isn't anything else they can do. If it is under warranty, it is thier responsibility to fix it period. If it is not under warranty, then I would say your friend is right, you cannot tell if a sealed bearing is bad just by looking at it unless it is completely wasted and comes apart. If there is a bearing that is so bad that it allows enough movement to damage gears, then I suppose a bearing problem is a possibility. However, if your problem is a bad bearing or two, and the dealer techs couldn't figure that out, then someone needs to be hit in the head with a big ass hammer. I am also wondering if the damaged gear in the t case is even related to the noise that you hear only when turning right? That seems more like a diff or axle bearing issue, I don't see how the two could be related. I think you have two different problems.

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the other mechanic from the fire station one of many of my jobs stopped by tonight to test ride the atv, at first he said it sounded like a bearing going bad but then after riding it around a little more he seems to think that the ring and pinion are just riding tight together which could be causing the noise. from standing behind me when i was riding he said he could hear it when i go both ways now right and left but said it is a lot louder when i turn to the right. so not sure what to do now, guess tomorrow will price it out to see how much it will cost to replace all the bearings becuase i find online i can get a whole new rear end for around $350

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I take it that this machine is not still under warranty. I would open the rear end up and just look inside. This way you can see if there is a problem with gear mesh or if it is just bad bearings.

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yea warranty ended few days ago, just waiting for a day off to tear it down will keep you guys posted

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so i finally got time to tear down the rear end. first thing when i drained the gear oil it looked like someone took a bottle of silver glitter and dumped it in the gear oil, there was so much metal in it. once got everything torn done everything seemed ok, the one bearing on the gear case side seemed like it had a little hang up in it, other then that everything came apart pretty easy. the only problem i am having now is getting the lock nut out that holds the bearing in front of the pinion gear. seems like i need a special tool to get it out because the lock nut is in the shape of a star which i can get no tool in to take it out.

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you can buy inverted torx socket sets from pretty much any automotive store. a complete set, metric and standard is approx $100.00. it is worth every penny to buy the complete set. As for the metal in your diff and the bearing that is slightly dragging, that is probably the bad one. I would replace all of the bearings in the rear diff and very closely inspect the gear set. If you put new bearings in, put in a bearing called ALL BALLS. they are a little bit more expensive but they are designed for severe use and abuse. you will be happy you purchased them. Congrats on the Diagnosis.

Your friendly neighbourhood Journeyman Mechanic :)

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well finally got that lock nut out after three hours now i can not get the needle bearing and ring stopper out, any ideas?

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you could use a 3 jaw inside bearing slide hammer. they are pretty slick little tools.

Your Friendly Neighbourhood journeyman Mechanic :)

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If the warranty just ended, I would have told that dealer that they need to figure out what the problem is before I stick a foot in someones backside. But I guess it's too late for that now. The inside bearing slide hammer is a good tool, heating the area around the bearing from the outside of the case may help too, the alluminum of the housing will heat up and expand faster than the steel bearing.

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yea well got the stop ring out but needle bearing is being a pain, i just noticed that the threads in the case are messed up from removing lock nut so at this point i think i am going to just buy a new rear end

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I would get it all apart and take it to a machine shop to fix the threads and any other pieces needed. To buy a diff is very expensive. the front diff on my machine is $1400.00 piece by piece. they did not make a drop in.

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The rear diff case is only about $100 from Service Honda. In fact, if you were to buy the case, ring gear, pinion gear, bearings, seals and a new lock nut, it would only cost you $429.75. That is if you even need all that. If your ring and pinion gear are ok, then you are looking at $217.62 for a new case, bearings, seals and lock nut. Here is a link to the site, just look up your machine my model # and see for yourself. Most front diffs are alot more complicated than the simple ring and pinion/solid axle setup that your Rancher has, there is no actual differential in that setup. Allballs has a good product, but OEM is usually the best bet for bearings IMO because of difference in error tollerance. Aftermarket bearings are more likely to not fit properly, low tolerance aftermarket bearings tend to be extremely expensive.

Parts Lookup with Accessory Lookup, ATVs, Motorcycles and More - ServiceHonda.com

Edited by DirtDemon

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I just looked up the parts and it depends on your model of rancher. just looked it up ring gear your price is $309.00. so make sure you have the proper info before you make your decision, or it could get even more costly than you expect.

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Gearhead, I think you may be mistaken there. There are 8 models of the TRX420 offered in 09. The TRX420FA and FPA are have a slightly different rear end. The other 6 are the same and in none of them does the ring gear alone cost $309, the FA; FPA ring gear is 123.53 and in all other models it is 106.57. I think what you may have been looking at is the whole final gear assembly, which is the case, ring pinion, all the bearings/seals, the side cover, bolts, shims, basically everything but the axle. It is the basically the whole list on the FA and FPA listed as item #3, and on all the other models it is everything you see outlined as item #10. On the FA and FPA models that whole package is 414.31 and for all other models, it is 307.35. I am glad you got me to take a second look at that because buying the whole final gear assembly as a package is cheaper than buying all the parts separately.

Edited by DirtDemon

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still waiting for the new rear end guys, as soon as get it and install it i will let you know what happens

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