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The car will be fine each morning or after sitting a while but when warmed up and I put it into drive the rpm's go up but the trans seems to not be going into first.
Recently replaced the bushings on shifter linkage. Also flushed the transmission for the second time since I got it in January. Fluid was a little bit dirty this time around but not like the first time which was pretty bad.
Using Valvoline Dex/merc tranny fluid. Ran 12 quarts through last week.
What causes the car to go into 1st gear without any issues when I manually put it in 1st but not when I put it into drive?
Thanks.
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replaced screen and gaskets with no leaks. no help to the problem. but a good exercise with the AW70. Worried that the transmission will soon not go into gear manually too. It seems to have shown a little slipping even while manually shifting. Which might do away with the idea I've had that maybe adding link bushings while changing the starter could have had some kind of an effect on the shifter.
Can a misadjusted shift linkage cause the car to not be shifted into D correctly causing it to have a hard to finding its gear out of N? Maybe I'm just not having the gear selector shift the trans correctly.
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In my opinion, there is nothing "useless", about cleaning the strainer/filter.
Yes, it is a hassle; you have to drain the fluid,remove the pan,etc. It's a messy task.
Why do I say this?, well,about 5 years ago, my 85 240 AW71 tranny started slipping, and I had a parts car, so I replaced the trans. with the one from the parts car...After completing this brutal task, I checked the strainer/filter on the original trans, and it was clogged...in other words, if I would have simply cleaned the filter, the original trans would have been fine....Switching trannys without first checking the filter/strainer, was one of the most idiotic and stupidest things I've ever done, and to this day I kick myself in the ass for not checking/cleaning the filter.
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I learned the easy way.
The transmission started slipping on my wife's 92 940 a few years back.
She was driving it to work and luckily made it the last 1/4 mile to the parking lot.
I went to look at it, cranked it up, put it into gear, and it drove away without any problems.
About a mile up the road, it starts slipping just like I had shifted into neutral. I cut the engine off and let it set for about a minute, cranked it back up and drove away again just like nothing is wrong.
Believe it or not, I knew immediately what was happening.
I drove the car the 15 miles to home about 2 miles at a time.
As soon as the transmission started slipping, I would immediately cut the engine and coast to a stop on the side of the road (luckily I live in the country), let it set for a minute and drive it away again.
When I got it to my shop, I drained and removed the transmission pan.
Sure enough, the filter was clogged with fibers...from the transmission clutches I suppose.
I cleaned the filter/strainer, and replaced the pan.
I then went to the nearest Wal-Mart and bought 3 gallons of Dexron II transmission fluid, took it home and flushed the transmission using the cooling lines at the radiator.
You can get the details on how to do this in the FAQ's.
That was about 4 years ago.
My son now drives this car, and there's been no problems with the transmission since.
These transmissions are almost bullet proof.
You don't want to drive the car with the transmission slipping, but it is possible to drive it a short distance the way I did.
I you were to just keep revving the engine without going anywhere, you would destroy the clutches in the transmission pretty quickly.
steve
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Thanks for the solidified response with what the next step should be. I dread having to drain the $50 of dex/merc I just flushed with but its worth it. So the entire transmission has to be emptied of oil? I thought the pan only holds 2 quarts of fluid. Does taking the screen off make the transmission leak the remaining fluid or can I just drain the pan? I'll be attempting this mess tomorrow with a chest aching from the shingles.
Lucky for me so far the trans will shift straight into 1st if I put it manually into 1st and then shift to drive after a few seconds. Once I do that its fine the rest of the time I drive it with no slipping at all.
Maybe I'll duct tape a plastic bag over my hair for this one.
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Does your car have a drain plug on the transmission pan?
If so...
I would catch the fluid in a clean container and re-use it.
You don't really have to flush the fluid again, you can just clean the screen and put the pan back on.
It will be apparent if a clogged screen is causing your problem.
If there are any remaining fibers floating in the oil stream, the screen should catch them.
You may have to clean the screen again if the problem returns.
hope this helps
steve
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It has the drain plug. I might just replace the 2 quarts and then hold on to the other 2 in the container of 4 for a possible later cleaning. I have a new screen kit that I bought for a past 245 I bought last year and sold to a brother. I'll keep the old screen around and maybe get a photo of it uncleaned. I'd like to get some magnets to add to the pan.
Today the shift into D was working fine until later tonight. Seems to clear up for a time or two here and there. Hoping tomorrow or Wednesday.
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You've flushed the transmission two times?
Did you remove the transmission pan and clean the strainer (filter)?
It sounds to me like the strainer is blocked with clutch fibers.
It does well after the car has been sitting for a few minutes, and then starts slipping after driving for a mile or two?
If it were my car, I would drain the pan and clean the strainer before I drove it another mile.
Just my opinion
steve
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Hi.
First, you didn't specify the year of your car. Up to and including 1983, you need type F fluid. Only for 1984 and onward should you use Dexron.
Second, are you sure you have the right amount of fluid. Usually, you shouldn't use the 90 deg scale because the fluid rarely gets that hot (if you use an IR thermometer on the underside of the transmission, you can get a good reading of the temperature, and you'll be surprised at how much cooler your fluid is). I find that interpolating between the two scales is more accurate, after the car has warmed up after about a half hour of driving.
There's not much else you can do, there are no external adjustments of bands or anything else that older domestic transmissions use to have decades ago. Also, according to your description, this is not a matter of adjusting the kick-down cable. And dropping the pan to clean the strainer (not a filter, btw) is usually a huge waste of effort -- although, if your transmission has a simple drain plug (some do, some don't), you can drain the small amount of fluid in the sump to see if any little chunks of debris are visible. You can do another flush, of course, and hope for the best. Given your description of how dirty the fluid was initially, maybe some irrecoverable damage has occurred, but you can still hope that a third flush will do the trick.
Good luck.
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Thanks for the help so far. I'm hoping its going to work itself back to driving fine. The transmission was driving so nice and shifting smooth when I got it. I'll be watching the level to make sure I've got it right. Would a lack of fluid cause this problem? Kind of strange that it started before the flush and I don't leak fluid.
Last resort is to watch the yards and look for a 940 with low miles or make a trip next spring out to CA and find a transmission out there. Or maybe even try a rebuild after getting my other 245's clutch and rear axle replaced.
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Although, in general, dropping the pan to clean the strainer is useless (and a TSB instructed that cleaning the strainer should no longer be routinely serviced), this is beginning to seem like a special case.
So I'll go along with Bruce ("Lucid") about suspecting that the strainer is becoming clogged with accumulated debris as fluid is drawn up through it.
But if only to save you the trouble before you know for sure, is there a way to drain the sump through a drain plug? I've seen some tranny's with a small plug, through which you could withdraw a sample and pour though a piece of paper to visually check for debris.
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"The transmission was driving so nice and shifting smooth when I got it."
When did you get it? And do you know it's history?
I'm picking up on HillBilly Steve's clogged filter screen thought here. And from what I've read, that symptom (disintegrating clutch fibers) can usually be traced back to coolant contamination several months (maybe a year or more?) earlier.
--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
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I got the car this past January. The past owners gifted me the car. They did have an issue with the coolant level going down and not being able to find the cause. I believe there was some of that stuff that people put into the coolant to stop a leak left over and gummed up on the bottom of the coolant reservoir. The radiator is a plastic one with a slow seepage along the drivers side. I'm hoping that the radiator didn't bleed coolant into the transmission. Sounds like the screen and radiator need to be replaced. I've already got a new screen and gasket kit sitting around. Thanks for the ideas and help.
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transit wind....Did you ever get the problem resolved? Did you check the filter/strainer?
Post back, that's how we all learn.
steve
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The last time we had this problem in the shop it was an AW71 and the valve body was sticking. a thorough cleaning cured the problem. It has been 2 years and the car has not had a problem since. Two clues , 1st trans fluid was very dirty and 2nd clue, it shifts in 1st gear manually. If the tranny cooler was leaking in the rad you should see swollen hoses and pink coolant caused by the ATF, or at a very minimum an oilly ring on the top of the coolant inside the expansion tank.
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More great news. I'll get to the screen asap.
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