I have a question for all the 4X4 guys out there.....I'm looking to buy a 4x4 in the near future and was wondering about downhill engine braking on these models. If you ride downhill in 4x4 on a brute force(or prairie) with the diff lock lever held in, will all 4 wheels slow you down? Same question for the Grizzly in diff lock mode and the Sportsman. (I heard that the Sportsman will just break with the rear wheels and that you end up sliding the **** end around when going down steep downhills).

 

On the ATV's, you don't need to hold the diff lock lever in for the engine braking, all 4 wheels will slow you down. Except for the Polaris, that is correct about the front tires not engaging and it can be very dangerous.

 

they say the engine braking on the brute force is very good and slows you down everywhere

 

If the two front tires have equal traction, either accelerating or deaccellerating, you have 4wd, on the prairie and grizz. If you were coming down a hill, that had loose rocks and sand, and had the diff lock on, you could end up with your hands full. With the diff lock on, its hard to steer and change diections.
About the only time you need diff lock, is when you stop making progress. As long as you are moving...you dont need diff lock.
Now there are some exceptions, like deep snow or deep mud, where having the diff lock on, helps to keep you moving.. You really only want the diff lock on, when regular 4wd wont get you thru.
On the polaris, you only get the front to pull, once the rears have started to spin. You wont get engine braking to the front. The polaris system reacts to wheel spin...all the others try to prevent loss of traction. The polaris doesnt have a differential in front, it has a spool. The hubs selectively activate and deactivate, when the system determines it should. All the others, the driver determines when its in 4wd or 2wd. Thats why Yamaha, calls there system, On Command. Because when you command 4wd, you will get 4wd, even downhill, around corners, and on high traction situations.
With the polaris, going to awd, with the switch, is still 2wd....until the back tires lose traction. Then the hubs lock up. Thats why its called on demand,
To answer your question about all wheels having engine braking ,.... on all but the polaris, you have 4wd engine braking, without the diff lock being on...provided the front two tires have equal traction.
The big difference on the prairie over the grizz, is if you are an agressive driver... the prairie can be activated , instantly, even with wheel spin. The grizzly's system needs to have the front two axles going the same speed to activate, which means you have to come to a stop, or at least have no wheel spin. The prairie can be activated at full throttle, as you feel you are losing momentum, say... thru thick mud, but on the grizz, you may need to engage it before going into the mud. Also the prairie s system is instant off( let go of the lever) but the grizz wont release, until there is no torque difference between the two sides, after pushing the diff lock to off.

 

I can’t comment on the Arctic Cat (never rode one) but I can for the other 3. The Brute Force has the best engine braking effect of all the others. Even when the Brute is in 2WD / high range it feels quite a bit better than the Grizzly in 2WD / high range when you let off the throttle when you are traveling at a decent clip. This was most notable when I was going downhill in a grassy field as the Brute felt much more composed and I never had to touch the brakes. Part of this may be due to the tires, if you really wanted to do an accurate comparison you’d need to have the same tires on all the machines.

One of my riding buddies has a Rubicon which has permanent 4WD and it has the best engine braking effect of any automatic that I’ve ever experienced. She does not like my Grizzly because of the inferior engine braking effect (when compared to her machine) because when going downhill on a grassy field (in 2WD / high) it doesn’t slow down enough for her and when she hits the brakes (she’s not accustom to accurate front / rear brake control) she ends up putting too much pressure on the back brake and ends up fishtailing (spooky for her and could be dangerous). However she tried out the Brute Force in the same situation (the very same hill) and was totally comfortable on it (even when it was in 2WD).

In slow, technical situations (for instance when going down a rough, steep hill) if you put the Grizzly in 4WD / low the engine braking is excellent (much better than when in 2WD / high and going faster). I haven’t yet tried the Brute in 4WD / low in a similar situation to compare it with the Grizzly.

As for the Sportsman it’s that slip sensing AWD feature that prevents the engine braking effect to be applied to all 4 wheels. When going downhill you never have a wheel spin situation so the front end will never be locked. Therefore any engine braking effect is applied to the rear wheels only. This is not necessarily a problem unless you are dealing with a steep, slippery downhill and in that case a fishtailing situation is very likely because the back wheels may end up breaking traction (locking up). This situation is further aggravated because of the Sportsman’s integrated (one lever does all) braking system. If you had an independent front brake you could apply some front braking pressure to help compensate, but with integrated brakes any braking that is applied may just end up locking the rear end which may already be on the verge of locking up because of the engine braking effect may be too much for the poor traction condition (unless you have an ABS braking system which I don't think Polaris does)...

 

Thanks guys for all your responses, and for clearing some things up for me. I have ridden the Polaris Sportsman and think it is an awesome quad, especially in the mud, but I have a lot of steep hill where I ride, and I don't know if I want to end up sliding down a hill if just the rear wheels brake.