Front ring and pinion break-in (1 Viewer)

[WarDamnEagle]

With any luck, in a few weeks I will have 2 new TRD elockers with 4.56 gears installed front and rear. I think I have a pretty good handle on the general procedure for breaking in new gears....drive a few miles, let cool, repeat, gradually increase distance and then change the gear oil.

That will work fine for the rear diff but what about the front? If I thought no one else was ever going to drive this 4Runner but me then I wouldn't worry about it as the gears would gradually get broken in over time as I use 4WD which would never be for a long distance. However, I have teenagers and I can just see one of them putting it in 4WD and driving a 100 miles until the paint burns off the front diff if the gears aren't properly broken in.

So how would you go about it? I could put it in 4WD with the hubs unlocked while breaking in the rear diff and I'm sure that would help some but I think to properly do it you want the axle loaded. Maybe that plus a few miles off-road in 4WD with the hubs locked?

So, the question is, what, if anything, have you guys done to break-in new ring and pinion gears in the front axle?

 

[Jonathan_Ferguson]

Never done it, never heard of it.

 

[KLF]

I just shift in and out of 4WD several times (hubs unlocked), the first time for about 10 miles, then gradually getting longer each time. I don't think the gears needs much load on them to get properly broken in, but a few trips off-road in 4WD won't hurt as long as you go easy on them. Try to keep track of the miles on them, then change the gear lube after about 500 miles.

That's all I did, and it's been fine.

 

[2ndGenToyotaFan]

I've always heard to do the rear, then pull the rear drive shaft, and drive it around in front wheel drive to do the front....

 

[rockrash]

Jack it up and put it on four jack stand,then run the rear for a couple minutes then engage the front and run it.If the fronts not a hi pinion then run it in reverse for a few minutes to make sure you get the bearings oiled good.Then put in 4th gear and run it for about 15 minutes then let cool and that sould be good for the front till you go wheeling.

 

[WarDamnEagle]

I've always heard to do the rear, then pull the rear drive shaft, and drive it around in front wheel drive to do the front....

I actually thought of doing that but thought to myself, "Now who would go to that much trouble?"

 

[toyminator]

You shouldn't really have to worry about any specific break in procedure for the front unless its a full time 4wd. The only reason for the rear break in procedures is to keep the heat down. Theoretically the front should never get that hot, just don't go on a 50 mile drive in 4wd for the 1st few months.

 

[lowtideride]

When you break in the rear just leave your hubs locked and it will break in the front as well. Dont have it in 4wd drive as driving on the street (dry) in 4wd drive is never really a good idea.

 

[2ndGenToyotaFan]

So you don't need a load on the front for a proper break in? Or are you just assuming the front will never see use like the rear?

 

[lowtideride]

I ran up the beach about 30 miles in 4wheel drive to break in the front set, after that I took it out of 4 wheel drive and just let the hubs locked as I broke in the rear set. That allows the ring & pinion to go through a couple of heat cycles.

My front ring & pinion never really see any high speed 4 wheel drive (as I dont rip thru the desert or drive in the snow anymore). So break in of the front wasn't a huge issue as heat is what kills them and it being used for low speed rock crawling.

Those set of 4.56 looked great even after years of hard wheeling with a locked front. They now live in another 40series crawler.

 

[fortysixandtwo]

When I got my 5.29s I asked my gear guy what the proper break in for the front was. His reply


"Don't hammer it for a while"

I drove it in 4 Hi, about 2 - 3 miles down a dirt road to the trail the first time I wheeled it. That was my break in.