Yup, me again. Just switched over to the Quaker State 4x4 semi-synthetic 10w40 oil for the engine, hoping for a little cooler running temps, maybe easier on the machine as well. I got to checking the front and rear diff fluids though, found the front to be fine on both machines, but the rear's were both a little low. Not sure if they came a tad bit low from the factory or what, but I'm going to change them out. I bought some Valvoline Dura-Blend semi-synthetic 80w90 gear oil for the diffs. Has anybody tried this before, or any semi-sythetic in the diff's for that matter? I kind of figured that since the differential fluids aren't changed as often, and are still subjected to high heat, that the synthetic blend would be better for it as well-reducing heat and wear. Any thoughts on this? I've heard the rumors that the synthetic's are bad on the wet clutch systems, yet in the diff's, I can't see how there would be any negative effect-what do you all think?

Thanks for the thoughts,

Mike

 

Hey Cowboy, synthetic oil is what has been in my diffs almost since the begining. I change mine every 3 months. Mine like yours was down slightly in the rear. I have noticed that it seems to lose a little between changes, although it has never appeared gray in color, so I assume there is no water present. It cost less than $5 to change both front and rear diff fluids and its about the same amount of work to check it as it is to change it.[ at least in the front anyway ]

Cheers Jim

 

Thanks for the reply Jim. Man, isn't that front check point a real pain to get back in! I guess it would be a lot easier without the stick stoppers on there, but still, kind of awkward getting your hand down in there. The rear is a piece of cake though, so that is definately a refreshing change. I'll go ahead and swap out my Dad's as well, as mine is already done.

BTW-cost on the Valvoline dura-blend was $4.49, cost for the quakerstate 4x4 blend was $2.59 per quart. Seems high considering you can get normal cheap oil for about $1.09, but for synthetic I guess you have to pay more. Still beats $3.50 for the AC oil!

Thanks again,

Mike

 

I changed out the front and rear diff fluid at 250 miles with Mobil 1 80w. We ride in a ton of mud and water so it was strictly precautionary. Not to mention it gets to 100 degrees around here at the drop of a hat. I wish I could say it did something outstanding but I can't tell. I do have some peice of mind which can be worth its weight in gold when your 125 miles from home or 20 miles from the nearest phone. You guys are right, that front diff is a pain to work on. I spilled more fluid on the floor than I got in it I think. I don't think you can go wrong with good diff fluid and regular maintence. Good luck guys!

 

Cowboy, my dealer told me that there wasn't any clutch's in the differentials. Maybe someone with a service manual could see for sure (just don't trust dealers). I tried to buy one with my bike, but he said he wouldn't sell it to me till after the warranty was up. I can see his reasoning. Still I don't think I would worry about the differentials if they had clutch's, because the clutch's are constantly applied. I know he told me to use any 80-90w hypoid gear oil.

 

Your dealer isn't steering you wrong. The AC front end doen't have any clutches in it. It uses a racheting cone system much like a rachet driver tool. Pretty simple system but very reliable.