Front Wheel Drive, Drivers side wont turn

longld · Post by **longld** » Fri May 11, 2018 2:13 pm

Jeep (53 M38A1) up on four jacks, 4 Wheel=IN, High/Low in Low, NO Warn Hubs installed, only original equipped wheel flanges installed.
I can manually turn one front wheel and opposite wheel turns in opposite direction. Startup the Jeep and only passenger side wheel turns, the drivers side wheel turns every once in awhile a few slow turns then stops.
Opened the differential cover, everything looks normal - to this Jeep beginner!

BTW, back wheels both turning fine under power.

Appreciate any help you guys/gals can give me. Tab on diff case says 43/8 (I believe). Believe it to be original front axle.

OKCM38CDN · Post by **OKCM38CDN** » Fri May 11, 2018 2:20 pm

Sounds like the Spider gears messed up (set of 4 gears in the center of the differential) I had one shatter and got the same thing...

Open the cover and move both wheels, all the gears should move...

longld · Post by **longld** » Fri May 11, 2018 2:22 pm

the cover is open and spyder gears look good! If I turn the wheels, both spyder gears turn.

Post by **wesk** » Fri May 11, 2018 9:31 pm

both spyder gears turn

Both = 2. You need 4 spider gears for the diff to work.

dpcd67 · Post by **dpcd67** » Sat May 12, 2018 10:58 am

That is normal; only the wheel that needs the power, turns, the other one doesn't. You don't have locking differentials. If you jack up one wheel and leave the other one on the ground, will the jeep move? No. All the power will be transmitted to the one that is "spinning". When you are driving it with all 4 wheels on the ground you don't notice it.
Why does your passenger side turn and not the drivers? It has the short axle and is easier to turn. If you held one of the rear wheels, only the opposite one would turn under power. They are both turning under no load but they aren't locked together.
If both wheels were locked together, you couldn't turn a corner. Hence the tern, "differential".

mdainsd · Post by **mdainsd** » Sat May 12, 2018 11:41 am

Plus one to above. To prove it out to yourself. Put a block under the passenger side tire. Repeat your test, now the drivers side will spin.

Post by **wesk** » Sat May 12, 2018 4:50 pm

Minus 1 to above. Non-posi diffs generally with both wheels off the ground, when you turn one wheel by hand the other wheel will rotate the opposite way. Yes, you can hold one wheel still while turning the other, but all you are doing then is exercising the spider gears. The only function of the spider gears on a non-posi diff is to allow either wheel to turn faster or slower as needed in a turn. On the other hand a posi diff when you rotate one wheel the other will turn in the same direction. If you hold one wheel still on a posi the other will free wheel if you try to turn it because the posi believes the held wheel has the traction.

mdainsd · Post by **mdainsd** » Sat May 12, 2018 6:39 pm

Well Wes, read his post again. O/P says "I can manually turn one front wheel and opposite wheel turns in opposite direction."

He also stated non pos diff. So it is behaving exactly like it should. If you put a vehicle with a diff like that in gear with the wheels jacked up the following three possibilities exist. Left wheel turns the other doesn't. The right wheel turns and the other doesn't. Or both wheels turn.

If the brake on one side drags a bit, it will be the opposite wheel that spins.

This is the definition of how an open differential works.

Post by **wesk** » Sat May 12, 2018 9:30 pm

My bad folks. I was concentrating on un-powered behavior of the non-posi diff and obviously you three are addressing powered movement off the floor.

Revisiting the original post I can see he has a drag issue on one brake. If the lengths of the axle were at fault the long axle wheel would never turn. His long axle wheel turned sporadically.

longld · Post by **longld** » Thu May 17, 2018 11:48 am

Thanks so much everyone! This has been driving me crazy - the other day I just sat there staring at the Jeep and wondering what to fix/tear apart. I think Wes is right, I might have a brake set a bit too close and will revisit. Time to get this Willys out of the air and driving thanks to all of you! I probably will never use the four-wheel drive but wanted it working regardless. All of you have saved me countless hours of frustration - hope I am able to repay it to the next neophyte that decides that rebuilding a Willys will be an adventure!

Now to order a diff cover gasket.....