Possible transmission Failure?
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elwesso
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Possible transmission Failure?
This hasnt really seemed to be much of a problem, until I started noticing more. The 1-2 shift is fine, but the 2-3 shift seems like there is a little slippage (it starts to shift, drops a little for a split second, and then goes down where it is supposed to be). Could this mean my transmission is about ready to go? The ATF was changed not too long ago, and I checked it today and it is in good condition. I dont know if they dropped the pan and replaced the filter. Would dropping the pan and changing the filter clear this up?
Sounds like slippage.Wes I am sorry to say it is rare for automatic transmission that display slippage to not need replcacing.
There is an off chance that that you have a constriction somehwere in your lines that causes your line pressure to drop and causes the slipage.
I would have the line pressure checked.A good tech look for a maybe clogged heat exchanger lines (if u dont have an aftermarket transmission cooler the stock set-up may eventually clog).Thats teh only possible cause of your slippage I can think of that can be fixed short of a transmission replacement.
But has to be checked <right away>!There are a couple of members here, that have saved their transmission by <right away> looking into clogged lines as cause of pressure fall/slippage.
Fred..
There is an off chance that that you have a constriction somehwere in your lines that causes your line pressure to drop and causes the slipage.
I would have the line pressure checked.A good tech look for a maybe clogged heat exchanger lines (if u dont have an aftermarket transmission cooler the stock set-up may eventually clog).Thats teh only possible cause of your slippage I can think of that can be fixed short of a transmission replacement.
But has to be checked <right away>!There are a couple of members here, that have saved their transmission by <right away> looking into clogged lines as cause of pressure fall/slippage.
Fred..
Its very dangerous to do a flush and skip the pan drop and filter replacment, as the fklush can kick up a lot of junk so u Need the pan drop.
Do a pan drop filter exchange in additon to checking the lines.A slipping transmission is always a <bad sign> but it may be possible to save it depending on the cause.
Fred..
Do a pan drop filter exchange in additon to checking the lines.A slipping transmission is always a <bad sign> but it may be possible to save it depending on the cause.
Fred..
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elwesso
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Thanks for the help! 1. How much should I expect to pay for a pressure check?? 2. What is the protocol if something is amiss?3. Should I drop the pan and clean the magnet and replace the filter?4. Since the ATF was changed recently (within the last 4mo), can I reuse the ATF? 5. If the pressure check is OK, how long can I expect to get out of this transmission?
1) I dont really know, it depedns on shop and what else they do at same time but its not real labor intensive so it shouldnt cost the world.
2)if lines are clogged, replace, maybe put in a transmission cooler to bypass a possibly clogged heat exchanger and/or lines.This also shouldnt cost the world.3) For sure,4) Depends on its appearance and what u find is going on.5)If it slips it could go anytime I doubt your pressure check will come out as good.
Remember we are hoping for the best case scenario w/ cheap fix with the above method.It is just as likely (more so actually) that your seals are shot due to an overheat at some point and this is cause of your slippage)The transmission could be shot, a good tech will be able to determine which it is.Keep in mind you also need an <honest> tech as the temptation will be tremendous for a shop, especially like an AAMCO. to say it needs. a transmission replcament vs just fixing a clog that may exist.
Good Luck friend and hope to see your Q alive and well at the Indy meet on the 28th.
Fred..
2)if lines are clogged, replace, maybe put in a transmission cooler to bypass a possibly clogged heat exchanger and/or lines.This also shouldnt cost the world.3) For sure,4) Depends on its appearance and what u find is going on.5)If it slips it could go anytime I doubt your pressure check will come out as good.
Remember we are hoping for the best case scenario w/ cheap fix with the above method.It is just as likely (more so actually) that your seals are shot due to an overheat at some point and this is cause of your slippage)The transmission could be shot, a good tech will be able to determine which it is.Keep in mind you also need an <honest> tech as the temptation will be tremendous for a shop, especially like an AAMCO. to say it needs. a transmission replcament vs just fixing a clog that may exist.
Good Luck friend and hope to see your Q alive and well at the Indy meet on the 28th.
Fred..
Also anythign beyond a pressure check will take taking out the transmission and opening it up.This will cost $$ at that point it may be a good idea to talk to Joe at infinitpartsusa.com for a good deal on a factoryt reman transmission, before going with a local rebuild thats likely to cost more and be less good.
Fred..
Fred..
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elwesso
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Ill take it in for a pressure check within the next couple of weeks. I only put about 10miles a day on it.
BTW, I went to advance auto parts, and saw some of the transmission additives that say they stop slippage, etc. One I was looking at was from lucas or something, and another one was slick 50 for trannys with over 50k. Would those help, not do anything, or even hurt the transmission? Also, i bought some air intake cleaner, by valvoline. I sprayed it in the lower vacuum hose right where intake hose meets the TB. Does it get sucked in by the vacuum hose before it reaches the plenum??
BTW, I went to advance auto parts, and saw some of the transmission additives that say they stop slippage, etc. One I was looking at was from lucas or something, and another one was slick 50 for trannys with over 50k. Would those help, not do anything, or even hurt the transmission? Also, i bought some air intake cleaner, by valvoline. I sprayed it in the lower vacuum hose right where intake hose meets the TB. Does it get sucked in by the vacuum hose before it reaches the plenum??
It can't be underscored enough - all slippage is bad.
Any automatic transmission has a number of clutch packs - usually four or five. The clutches release by spring pressure and are engaged by a hydralic pistion pushing the clutch faces together.
The clutches are connected by differernt drums with plantary gears and shafts. By engaging the right combination of different clutches a gear ratio is created.
The clutch faces are NOT like the clutch in a manual transmission. These are thin steel sheets with a rough suface glued on. The design is that the clutch grabs almost immediately with very little slipping. Every time the clutch engages there is some slipping. The two rough sufaces work against each other like sand paper, wearing tiny bit off.
The faster the piston drives the clutch together, the "harsher" the shift (it kicks more), but the less slippage and less wear.
Eventually in all automatic transmissions the amount of wear on the rough surface begins to affect it's ability to hold. Once the slippage rate starts to increase from a few 10/ths of second to several seconds - the wear rate increases quickly. Soon it's just bare metal against bear metal and the clutch loses it's ability to transmit force and the transmission fails.
Low pressure in the power lines kills a transmission quickly because the piston can't drive the clutch pack together quickly enough, or not strongly enough. Slippage and wear quickly result. Low pressure can result from a plugged filter, plugged passages, low fluid level, air in the fluid (caused by too high fluid level - the moving parts whip the fluid into a froth)
In your case, it sounds like the fluid may be too thick when cold - pointing to either old fluid or a contriction someplace (hot fluid flows better thorugh clogged passages)
Any automatic transmission has a number of clutch packs - usually four or five. The clutches release by spring pressure and are engaged by a hydralic pistion pushing the clutch faces together.
The clutches are connected by differernt drums with plantary gears and shafts. By engaging the right combination of different clutches a gear ratio is created.
The clutch faces are NOT like the clutch in a manual transmission. These are thin steel sheets with a rough suface glued on. The design is that the clutch grabs almost immediately with very little slipping. Every time the clutch engages there is some slipping. The two rough sufaces work against each other like sand paper, wearing tiny bit off.
The faster the piston drives the clutch together, the "harsher" the shift (it kicks more), but the less slippage and less wear.
Eventually in all automatic transmissions the amount of wear on the rough surface begins to affect it's ability to hold. Once the slippage rate starts to increase from a few 10/ths of second to several seconds - the wear rate increases quickly. Soon it's just bare metal against bear metal and the clutch loses it's ability to transmit force and the transmission fails.
Low pressure in the power lines kills a transmission quickly because the piston can't drive the clutch pack together quickly enough, or not strongly enough. Slippage and wear quickly result. Low pressure can result from a plugged filter, plugged passages, low fluid level, air in the fluid (caused by too high fluid level - the moving parts whip the fluid into a froth)
In your case, it sounds like the fluid may be too thick when cold - pointing to either old fluid or a contriction someplace (hot fluid flows better thorugh clogged passages)
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elwesso
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VERY GOOD POST!!! It clears up a lot. I know the transmission was flushed or at least the fluid was changed not too long ago, but the question is if they dropped the pan and replaced the filter. It actually has seemed to clear up a little, after a WOT run. I will get a new filter soon and replace it.
Is it an easy job (or as easy as it sounds), is it really a matter of dropping the pan (after draining the fluid), and unbolting the old filter and replaceing the new one. In which case it would be like a 30min job??
Is it an easy job (or as easy as it sounds), is it really a matter of dropping the pan (after draining the fluid), and unbolting the old filter and replaceing the new one. In which case it would be like a 30min job??
splash!
it's easy, but messy. Drop the pan, the filters' right there, couple a bolts. Scrub that pan out, it will be loaded with sludge - mostly clutch wear from the first 1000 miles.
Not all first gen Q's had drain plugs. Dropping fully loaded pan can be VERY messy. Getting the car on lift makes the job much easier.
Oh - and I should mention that in an automatic - all "looseness" should happen in the torque converter - it provides the buffer between the engine and the driveline. Think of it as two box fans face2face - one side is driven by the engine and turns the other. At a dead stop in first gear - everything in the transmission is stopped moving except the torque converter is doing all the slipping (of course the transmission pump is connected through the converter and always runs at engine speed)
dan
Not all first gen Q's had drain plugs. Dropping fully loaded pan can be VERY messy. Getting the car on lift makes the job much easier.
Oh - and I should mention that in an automatic - all "looseness" should happen in the torque converter - it provides the buffer between the engine and the driveline. Think of it as two box fans face2face - one side is driven by the engine and turns the other. At a dead stop in first gear - everything in the transmission is stopped moving except the torque converter is doing all the slipping (of course the transmission pump is connected through the converter and always runs at engine speed)
dan
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elwesso
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If im not mistaken, i think the 94s had one..... Ill try and avoid labor charges to have someone do it, and i dont know anyone with a lift.
So ill have to improvise or have someone do it..... Would it be worthwhile to go ahead and get new fluid, or can i reuse the old stuff.
Do you think that if I got a filter, i could take it to an independant shop and have them do it, since they would have a pan to catch all the fluid, and a lift?
So ill have to improvise or have someone do it..... Would it be worthwhile to go ahead and get new fluid, or can i reuse the old stuff.
Do you think that if I got a filter, i could take it to an independant shop and have them do it, since they would have a pan to catch all the fluid, and a lift?
always use new fluid. Don't even think about trying to reuse the old stuff (even if you just changed it a few weeks ago) The contamination risk it pretty high, and you'll be doing a favor to "reflush" the transmission.
The biggest problem about the mess is that transmission fluid stains and is near impossible to get out of concrete.
your 94Q will have a drain plug.
The thing about the lift is clearance. If you jack the car up 2 ft on stands - thats looks pretty high, but once you slide underneath it makes for a pretty tight enviroment to be lifting a heavy pan up and down in. I personally would do it myself in the driveway using a tarp to contain any accidental spill and put the money I saved into new synthetic oil.
Most shops shouldn't oppose a customer bringing in parts - especially if they are dealer parts. If they bill labor and parts seperately on an invoice, they should accept not being the sole parts supplier.
The biggest problem about the mess is that transmission fluid stains and is near impossible to get out of concrete.
your 94Q will have a drain plug.
The thing about the lift is clearance. If you jack the car up 2 ft on stands - thats looks pretty high, but once you slide underneath it makes for a pretty tight enviroment to be lifting a heavy pan up and down in. I personally would do it myself in the driveway using a tarp to contain any accidental spill and put the money I saved into new synthetic oil.
Most shops shouldn't oppose a customer bringing in parts - especially if they are dealer parts. If they bill labor and parts seperately on an invoice, they should accept not being the sole parts supplier.
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elwesso
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Thats weird..... I was going to buy some tockico blues and have an independant shop put them in that my family has delt with forever.... But they dont seem to want to do it.. Should I try elsewhere? And if the only thing is to worry about is a mess then that is the least of my problems. I think this is something I can handle!!!!
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Q45tech
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"If they bill labor and parts seperately on an invoice, they should accept not being the sole parts supplier."
At T3 we make roughly 20-30% on factory parts [buy at discount sell at retail - what dealers sell at].Since the average job is 54% parts and 46% labor........every average hour is roughly $150 gross ..........without the profit from parts we would have to charge $90 per Book hour to net the same.........instead of $68!
We do offer a $1000 per day flat rate where you get the techs full atttention with YOUR PARTS from 8AM to 6 PM.......generally a master tech can do 12 BOOK Hours in a day..........a saving to the client of 8%.Same with junk yard parts we just charge $90/hr and install what you bring, however you must deal with the part warranty your self.
Not a great idea with something like a transmission since you have to pay for removal, shipping, and wait a week or two for a replacement then pay again for another install. Even the factory remans occassionaly fail in the 12 month period......a bad run does occur.
Just remember when you supply your own parts to offer to pay more in labor that way the shop will not take a loss on having your business.
At T3 we make roughly 20-30% on factory parts [buy at discount sell at retail - what dealers sell at].Since the average job is 54% parts and 46% labor........every average hour is roughly $150 gross ..........without the profit from parts we would have to charge $90 per Book hour to net the same.........instead of $68!
We do offer a $1000 per day flat rate where you get the techs full atttention with YOUR PARTS from 8AM to 6 PM.......generally a master tech can do 12 BOOK Hours in a day..........a saving to the client of 8%.Same with junk yard parts we just charge $90/hr and install what you bring, however you must deal with the part warranty your self.
Not a great idea with something like a transmission since you have to pay for removal, shipping, and wait a week or two for a replacement then pay again for another install. Even the factory remans occassionaly fail in the 12 month period......a bad run does occur.
Just remember when you supply your own parts to offer to pay more in labor that way the shop will not take a loss on having your business.
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maxnix
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1995 Infiniti Q45t
2000 Infiniti Q45
Complete Fluid Replacement vs. Partial Fluid Replacement
A flush and a drain are in no way comparable even if you drop the pan and replace the screen.