Drag while turning drive wheels?

[J R Jones]

I am the third owner of a 2014 818. The donor is a 2002 WRX with ~132K miles.
Most of the rework and assembly was done by owner #1 and I have never had a link to him.
It has always been a hassle pushing the chassis as there is a substantial amount of drag. I assumed it was (Wilwood) brake drag on the rear axle.
Today I said "enough" and pulled the rear calipers; that changed nothing, so the drag is in the transaxle.
Either left or right (apparently no traction lock) will resist, then turn with effort. There is a slight hissing noise as the wheel/axle turns.
With no experience in this assembly my intuition is the drag is not normal. OTOH I expect only the differential and main shaft are turning.
I assume the 2WD rework does not require a change to the ring/pinion, so unusual gear preload should not have happened.
Let me know if this condition is typical, or what problem may have been induced during rework.
jim

[lpmagruder]

Turning the rear wheels feels about the same as it ever has turning the front wheels of a Subaru, there's always been a decent amount of drag, but they should spin without a ton of effort.

[Bob_n_Cincy]

Let me know if this condition is typical, or what problem may have been induced during rework.
jim

Jim, I push my car around the around the shop floor often. It only take 20-30 lbs of force to roll it and then i have to pull back to stop it. Same as or less than any other car. If the original owner put an LSD (Limited slip diff) into the transmission he would have had the transmission completely apart. This would also require adjusting the ring-gear preload.
Bob

Jim, I didn't understand this sentence in your post. "Either left or right (apparently no traction lock) will resist, then turn with effort." Please explain.

[lance corsi]

I think he means that his car has an open differential.
Is it possible that the previous owner changed axle seals? If so, the pinion spacing may not be correct. The symptoms sound like an improperly spaced crown gear.

[J R Jones]

Jim, I push my car around the around the shop floor often. It only take 20-30 lbs of force to roll it and then i have to pull back to stop it. Same as or less than any other car. If the original owner put an LSD (Limited slip diff) into the transmission he would have had the transmission completely apart. This would also require adjusting the ring-gear preload.
Bob

Jim, I didn't understand this sentence in your post. "Either left or right (apparently no traction lock) will resist, then turn with effort." Please explain.

Bob, The drag is experienced with either L or R rear wheel, and when one wheel turns, the other wheel does not. My assumption is the differential is open.

Lance, This feels and sounds just like brake pad drag, not like seals that I have experienced.

Could improper axle length pre-load the differential?
Thanks

[lance corsi]

To be clear, I’m not suggesting that the axle seals are causing the problem, it sounds more like a seal flange may have been over tightened, reducing pinion-to-crown gear clearance. Try backing off first one flange, test, if no improvement, return flange to original position, then try backing off the opposite side flange and repeat the test. Obviously, put a mark on the flange/case interface to reference.
Unfortunately the flange design requires removal in order to replace the seal. The flanges may not have been returned to their original positions. This would affect crown gear clearance.

[J R Jones]

To be clear, I’m not suggesting that the axle seals are causing the problem, it sounds more like a seal flange may have been over tightened, reducing pinion-to-crown gear clearance. Try backing off first one flange, test, if no improvement, return flange to original position, then try backing off the opposite side flange and repeat the test. Obviously, put a mark on the flange/case interface to reference.
Unfortunately the flange design requires removal in order to replace the seal. The flanges may not have been returned to their original positions. This would affect crown gear clearance.

Yikes I would not anticipate that assembly procedure, thanks. (what could possibly go wrong?) Might I need balanced unloading on each side?
I am swapping body/cart and rolling chassis between my shelter and the garage for the winter requiring organization on both ends. This would be easier if it had not (lightly) snowed for the last three days.
"Organization" always creates recycling as I evaluate the inventory. Today is dump and recycling day plus the swapping so testing your hypothesis may be delayed to tomorrow.
jim

[Bob_n_Cincy]

Bob, The drag is experienced with either L or R rear wheel, and when one wheel turns, the other wheel does not. My assumption is the differential is open.

Jim, When both wheel are up in the air and you have an open diff. The ring gear could be totally frozen , then turning one wheel should just rotate the other wheel in the opposite direction. Bob

edit: Maybe you have a wheel bearing issue.

[J R Jones]

Bob,
That is a little confusing (frozen ring gear). Yes the chassis was on stands and yes the opposite wheel does not turn when either wheel is turned.
I do not have transaxle experience but in conventional RWD drive, the transmission output shaft does not decouple from the differential in neutral. Therefore my concern that the drag could be in the output shaft.
jim

[Bob_n_Cincy]

Put the car in gear and then try and spin the wheels individually. This will prevent the ring gear from turning. If you still feel resistance. The only parts moving are the wheel bearings, axles and spider gears. Bob

[J R Jones]

Put the car in gear and then try and spin the wheels individually. This will prevent the ring gear from turning. If you still feel resistance. The only parts moving are the wheel bearings, axles and spider gears. Bob

Bob, I used your suggestion but did not succeed. The shift shaft thrusts in and out (3-4) and in both those selections the engine turns with the wheel(s).
Suspecting an internal issue I checked the gear oil, it is between the OEM marks, so low as I understand, because the transaxle is not at OEM angle. Could be dry parts have corroded?
With all this wheel turning the drag has become ~10-20% easier, but is still accompanied by a dry dragging sound.
An additional issue, or perhaps colateral damage, the shift shaft will not turn. The transaxle may have influenced owner #1 to bail out.
jim

[Bob_n_Cincy]

Bob, I used your suggestion but did not succeed. The shift shaft thrusts in and out (3-4) and in both those selections the engine turns with the wheel(s).
Suspecting an internal issue I checked the gear oil, it is between the OEM marks, so low as I understand, because the transaxle is not at OEM angle. Could be dry parts have corroded?
With all this wheel turning the drag has become ~10-20% easier, but is still accompanied by a dry dragging sound.
An additional issue, or perhaps colateral damage, the shift shaft will not turn. The transaxle may have influenced owner #1 to bail out.
jim

Jim, with the car in the air and you turn one wheel and the engine turns and the opposite wheel does not turn. The only possible problem is that the hub wheel bearing has a lot of friction it it. I can only suggest that you remove your half shafts and check your hub bearings.
Bob

[J R Jones]

Bob, Turning the engine with the axle added turning load and a slight bit of noise but I do not hear noise from the (unloaded) wheel hubs. They would have to be similarly failed as the drag is not different L to R with the opposite wheel on the pavement. I prefer a simple solution but I suspect the transaxle.
Perhaps I will jack the chassis to make the transaxle level and slightly overfill it. Then I will pull the plugs and spin the assembly with the starter motor to see if I can free things up.
jim

[J R Jones]

Jim, with the car in the air and you turn one wheel and the engine turns and the opposite wheel does not turn. The only possible problem is that the hub wheel bearing has a lot of friction it it. I can only suggest that you remove your half shafts and check your hub bearings.
Bob

Bob, I leveled the transaxle and it took a quart to bring it to full on the dip stick. I brought the rear axle up and listened carefully to the drag noise. It was at the hub but sounded like brake pads. I pulled the wheels and calipers looking for interference. I noticed the hand brake cables. I had not considered that system in the work I have been doing. Indeed the new Wilwood brake rotors would not come off. The shoes were set too tight and more than that, the Wilwood drum edges drag on the backing plates. Without the rotors, no drag. I am reworking as necessary.
Not the first assembly error I have found. Thanks for your help.
jim