I’m in the process of tearing down my Subaru transmission and wanted to give a brief overview of how they work. Forgive the poor memory for correct terms!
Thanks for the explanation just a question on the center diff ? does it link directly to the front and the disks inside transfers power to back differential?
Hi quick question do you have a idea why the transmission would stick in 5th, could the center differential cause the problem? Because I have it all pulled apart and the bearing on the center diff had exploded I’m just trying to find if the center diff failing could cause trouble shifting out of 5th at slow speeds or if it is part of the shift fork?
Nice video! Could you maybe explain why my eudm forester SG XT 5MT has a transfer reduction (at the center diff) of 1.081 instead of 1? It also seems to have a 4.444 front diff ratio and a 4.111 rear diff ratio. The only thing I can think of is that there is a difference in torque sent between the two diffs, but I don’t know… an explanation would be awesome. Thank you!
Can you find your serial number on this chart? www.rallispec.com/downloads/Transmission%20ID%20Chart_Public.pdf having the steeper front diff ratio would make it a produce a little less stress on the gears for the front wheels, the transfer reduction would then make the rear wheels turn at the same speed as the front with those ratios. perhaps with the heavier forester the strain was too much on the small shaft that runs from the center diff through the hollow shaft the gears are on to the front differential. Making that differential steeper would lessen the strain on the shaft and the gear reduction behind the center diff would make the wheel speed the same between front and rear axles.
@Scott Briscoe Sorry of this is a noob question. But why is the output shaft that is going to the rear differential not connected directly to the centre differential but instead via an intermediary?
I believe it's because not every Subaru used a 1:1 transfer reduction so doing this allowed them to put different gear ratios here. this enabled them to put the same transmission in a variety of vehicles without having to reengineer everything.
Hey Scott. I’m having a problem with my manual transmission from Subaru forester 2011. The problems is just when it gets hot. When I’m doing turns it makes a cracking noise I hope you can help me. Thanks in advance
Interesting, why would they put the two gears after the center diff. I read one of the previous comments that they are used to get the ratio correct but why wouldn't they just put matching diffs both sides. Either im missing something or these gears seem a bit redundant.
I think it gives the factory optionality- maybe there was a time where they couldn't get the gear ratios they wanted for front or rear diffs and so they developed this- it's been in subaru transmissions for over 20 years now. Also- it could be that they use it to change the output shaft height to give more ground clearance. I'd be really interested to know from an engineer as I'm just guessing!
Hey there i have a 5-speed manual 2004 Impreza Outback N/A that i bought for my son as a first car. Test drove it for 500 miles and it seemed fine. Tagged it for legal driving and 200 miles later i have some kind of binding click noise that happens randomly, but more often when the tires are operating on muddy snow terrain. I can feel the clicking in the stick shift handle. The tranny gear oil was about 1.75 qts low. I filled it and sound is a little less present but still present. Is the center differential lubed by the same gear oil reservoir as the manual transmission? What do you suggest to do? Thanks!
I would almost bet that it's the center differential. They often heat up and can bind up when they fail- it's most noticeable on terrain like you describe or when turning very sharply like in a parking lot.
@@boostedego6043 4th looks like the synchro would be easier to replace as it's on the input shaft side so you don't have to mess with the pinion depth adjustments. It might be easier to buy a used transmission and replace the input shaft from it into your transmission. But this is definitely not for the faint of heart either way to repair this!
Sorry didn’t see your comment earlier. I buy my parts from Arapahoe Subaru online. Anything inside the transmission I buy oem. parts.autonationsubaruarapahoe.com/?dealercode=090342
