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2 noob question about dropping the tranny

868 Views 15 Replies 9 Participants Last post by  salvadoran300zx
So I finally decided to take down my tranny for the first time, but I got two questions actually...

First, when I finally remove all the bolts will the clutch hold the main shaft and the whole tranny in place, or will it want to fall off as soon as the last bolts are removed?

second, when torquing the upper bolts how does the torque meter and the universal joint get along? will it be the same reading? I would suppose that some torque strength is lost on the joint itself and on the length of the extension
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The main shaft will hold it in place, yeah. When I've taken mine out, I have used both the transmission mount and a jackstand/2x4 to hold it up to keep pressure off of the input shaft until I'm ready to drop it out finally. Also, for the top bolts some people like to use 8 million feet of extensions and u-joints. I've found that if you can get your arms up in there, try hugging the transmission and using a gear wrench. Maybe even have a little brother or someone with smaller arms do it?...

Good question on the torque wrench. I think I read somewhere that if what you're torquing isn't DIRECTLY underneath the head of the torque wrench(in your case off centered by u-joints), then torque values will be changed. Might want to wait till one of the older guys posts for that info though. In honesty, the I use a torque wrench on all the bolts I can easily reach on the bottom and use my best judgement for the bolts on top. In 3 transmission pulls, I've not lost any bolts and have had no issues....to each their own though. Good luck with it!
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Thanks! I had heard of the "hugging to get top bolts" technique before, but these chubby arms of mine always have troubles getting through =P

So I'm off to buy another 10" worth of extensions and a new 3/8 ratchet.

Thanks for the input! I was afraid it might just drop or put too much pressure on the disc/pressure plate to mess something up.

Thanks again!
Just make sure you don't pull the trans out a few inches and then let it hang there too long, that can bend the fingers of your pressure plate.
I found this, kinda cool, but i dont think its what you mean.
http://www.specialpatrolgroup.co.uk/spooky/torque/torque.html

But from what i understand it doesnt matter if there is an extension to the socket, You're applying a torque at one end, and the bolt is applying a counter-torque at the other end. If the extension is not in the process of being twisted to a greater extent then it already has been, then the torques at both ends must be the same in magnitude but opposite in direction. (If the torques were not equal, the extension would be twisting more.) Then by Newton's third law (more or less), the torque being applied by the socket to the bolt is the same as (but opposite) as the counter-torque being applied by the bolt to the socket.

and if the torque wrench does not line up with the head of the bolt it will not be as accurate, but im not to sure how to calculate that, but i honestly dont think you have to worry about it..

When I droped my trannie i just stuck my 2.5 ton jack under it, and rolled it back when all the bolts were off!
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You're applying a torque at one end, and the bolt is applying a counter-torque at the other end. If the extension is not in the process of being twisted to a greater extent then it already has been, then the torques at both ends must be the same in magnitude but opposite in direction. (If the torques were not equal, the extension would be twisting more.) Then by Newton's third law (more or less), the torque being applied by the socket to the bolt is the same as (but opposite) as the counter-torque being applied by the bolt to the socket.
WOW!!! :eek:

These are the kind of explanations I really like! Scientifically backed up but not as much and deep that I can't understand =P THANKS!

So in other words, we might assume the same thing of the universal joint, after all it won't twist dampening any of the forces.

Thanks also for the tip of not letting it hang to bend the fingers on the pressure plate!

Wish me luck guys! I'm diving into it right now! (much more confident now) 8)
The torque applied to the shank of the bolt or nut on a stud will be roughly equal to the cosine of the angle. If you had the extension/swivel at a 45 degree angle, and if the socket would stay on the hex of the bolt or nut without popping off (which is will pop off), .707 of the torque value would be going to tighten the nut and the other .707 of the torque value would be going to side force on the nut/bolt. To sum to a torque of "1" indicated on the wrench, it would be the sum of the squares of the sides equal the square of the hypotenuse (long side = 1).
.707 squared = .5; .707 squared plus .707 squared euqals 1 sqquared = 1.

So unless you have a really steep angle approaching 45 degrees, you can add a little torque to the value needed.

If you've ever used a ratchet with an extension, a u-joint at an angle, and another extension, you know how much the universal wants to jump out of position, because part of the torque at an angle pushes out and part goes to the target. Even if you hold the u-joint in place the side force is still against the piece holding the u-joint.

http://www.algeo.com/~joe/KIAT/kiat_3.htm
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Please take pics! so other noobs like me can follow your lead!

I may be dropping my tranny next year or two!
If you remove the trans mount, it makes the top bolts a lot easier to get to.
@ dumbestone: thanks for the math lesson! It does make quite a bit of sense but I guess it would be hard to apply in real life, so I'll go ahead and use my best judgement

@ elcid: on the bad side, my camera decided to take a dump a while back and haven't gotten around to getting a new one yet, but on the good side, there's plenty of write-ups with pics and everything, if you scroll down a bit more you'll see another post of mine where I was asking for the write up and there's a very useful link to how to do it

@ kandy: thanks for the tip, I'll get to that right after lunch and after taking out the friggin' one piece driveshaft which is stuck to the diff like it was born there :mad:
Hit the driveshaft with a rubber mallet
manual NA tranny weighs approx 95lbs, TT weighs about 130lbs. Man up =P Theres a certain individual on this board whom i've seen drop that bitch on his chest and wrestle it out by hand
Luminar said:
manual NA tranny weighs approx 95lbs, TT weighs about 130lbs. Man up =P Theres a certain individual on this board whom i've seen drop that bitch on his chest and wrestle it out by hand
DON'T try that! hahaha!!! I had read the same post that it was possible to manhandle the thing out... dumbest idea ever! LOL!

I thought I could do it, since I could handle the other one no problems, you know pick it up, drop it in the trunk of a car and so on.... but being in that tight space and just right under it makes it a totally different ball game! LOL! in all seriousness I panicked for about 5 seconds when I felt the weight of it on my bare hands... once I laid it on me to land it to the floor the panic was over =P

but definitely not a nice experience for noobs... so piece of advice get yourselves a floorjack and mod it to be a tranny jack =P
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I normally pull transmissions out alone...but last fall i was pulling my Toyota trans out, which is very similar in size/weight on the TT trans. Well I though it was secured, so i let go of it to take a break, 15 seconds later the trans fell on my head. Fisrt time ive ever been to the hospital in 26yrs and a few stitches also! Be careful when taking the trans down..just sayin.



Face is Swollen :)
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Several things on making the tranny pull a bit easier....

- Tranny should in neutral if a 5 spd before starting this job.

- Use a jack on the rear of the tranny to support it when removing the rear support bracket. Jack allows the tranny to be tilted up/down to give better access room for getting to bolts and for accessing connectors on top of tranny, etc. Note: Some people pull the engine with the tranny attached - so the tranny really doesn't need any add'l support from the rear (it can just hang). But you don't want it just hanging when trying to undo the bolts.

- Tranny jack like what they sell at Harbor Freight for around $80 is a good way to go. Have this one:
http://www.harborfreight.com/450-lb-capacity-transmission-jack-39178.html

- If you use this jack -- use a small wood shim to wedge under the saddle where the tranny sits a little high. Also buy a 2nd strap from Home Depot -- that single strap isn't enough to keep things totally wiggle free. You won't mind giving the jack a good yank to break it free from the engine. Suggestion of the shim is for keeping the tranny sitting on the jack saddle just as it did when attached to the engine. It really does help.

- Before undoing the bolts, jack up the engine/tranny connection point just a little bit. It takes some of the pressure off the bolts and makes them easier to undo. Once bolts are loose - hook up the tranny jack.

- Whenever jacking anything, use a small piece of wood (3" x 4" x 3/4" or similar) between the jack and engine part. It distributes the load better.

- No need to drain any tranny fluid if using the jack and keeping things mostly level. It takes a bit of a tilt to get fluid spilling out of the drive shaft opening. However, you will need to drain the fluid if the tranny is being serviced or moved around off the jack. Easier to drain fluid while tranny is still attached to the car.

- When re-installing the tranny, helpful to take a 2 long metric bolts (Home Depot, etc) - cut off the heads and Dremel a screwdriver head slot. Bolts act as guides for allowing the tranny to slip on the engine bracket - screw heads allow them to be easily removed. I found just 2 bolt - one on each side got the job done. Others have used 3 or 4 but I'm not sure why that many are needed? Good idea to lube them up a little too.

- Pay attention to how the engine tilts AFTER the tranny load is removed. Look at it from the engine bay top BEFORE undoing the tranny and with a piece of tape mark a reference point. This is how you want the engine to be sitting when trying to re-mate the tranny. Makes alignment, even when using a tranny jack easier. REMEMBER - Do any jacking with a piece of wood to distribute load more evenly.

- Don't worry about bolt torque for the higher placed bolts. Just do by hand and call it a day. Don't forget to re-attach the battery ground strap to that high bolt on the psngr side either. Pain in the butt to get the bolt done and then realize you didn't fasten down the strap.

- For the battery/harness cable bracket that sits above the ground strap but is fastened to the back of the engine block. Easier to get that bracket back in-place by using a piece of tape to hold the 2 halves together. Less struggling to get the bolt into place -- pretty sure I used a longer bolt too (plenty of room for it to fit).

- FYI: Posted this last night to another question. Another really helpful piece of gear --- but a car OEM or a rolling jack will do too:

One of the most useful things I purchased from Harbor Freight besides a tranny jack was a 12v electric scissors jack. The flimsy plastic saddle broke almost right away but it didn't matter. Once off (and rivet is removed) the jack has a nice flat surface for jacking up frame rails, putting a little tension on the tranny while removing the tranny to engine bolts, etc. We have used this thing so many times over the last year for various car jobs -- well worth the $60 or so it costs. I'd actually recommend removing the saddle right from the start and using it that way. I'm thinking about fab'ing a little metal saddle (block) for times when I really need to use it that way but those times haven't been very often so far ...

This is the idea: http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&productId=100637530&langId=-1&catalogId=10053&ci_sku=100637530&ci_src=14110944&cm_mmc=shopping-_-googlebase-_-D25X-_-100637530&locStoreNum=906
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you know guys... now that I think about it... if I were to do this stupidity again, I would try laying across it and not inline with it, like if I were to bench press it out placing my stronger arm on the fat side of the bell housing and have someone else to balance it out as I lower it.

About draining the fluids, jzack is right, its much easier to do while still on the car. My oil looked like mud and I picked up residue of what used to be a synchronizer... so much for a "fresh" rebuild.

But on a safer note... for those of you who can get that tranny jack on HF, go for it... totally worth it!

now, on to taking out the pressure plate... hope there are no surprises there!

p.d. would you recommend loosening it by hand or use my impact wrench on it? :p
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