OK, get your mind out of the gutter ! Well after fixing the bogging problem , next day.....BAM ! when It shifts from 1 st to second ONLY, the other shifts are smooth , as the always were.
Is there a modulater valve of some type ? seems odd to only happen from 1st to 2ed and it started suddebly.
'86' van auto trans. 2wd
U-joints or worn ring & pinion gears in diff
It's all that extra HP tearing up your rear-end. It might be a failing universal joint. While sitting still, foot on brake, shift from D to R & back again while listening for a clank. You might also try that while somebody is watching the drive shaft. Compare movement between front & rear joints. If one moves more than the other, then I'd replace. 84 & 85 vans have replaceable joints, so at least there's that.
This could also be caused by a harsh shifting problem due to worn or shrinking check balls inside the transmission valve body. Here's a thread where this was recently discussed: http://www.toyotavantech.com/forum/s...1370#post11370
U joints are good, that's the first thing I checked. But I was doubtful, because like I said,. it only happens when shifting from 1st to 2ed, not a 'clank' either. and it started suddenly, I thought I had just ran over a speed bump to fast !
I don't want to even think about pulling the tranny.
Been noticing that my transmission seems to get kind of funky after about 5 or 10 minutes of operation from cold start. Very obvious downshift where you can feel it just drop and slow down, then adding more accelerator she will clunk. It is worse as I use the OD. But again she is fine when cold. Any chance the ATF is getting too hot? Not sure, 10 minutes isn't that long and it is still cool here.
One more thing I missed in the last thread, it clunks when I back off on the throttle. I checked my kick down adj and it seems to be where it should be as per the manual. The cable seems to move ok. If I manually pull on it and let it go she will retract to the stop clamp mounted on the cable
A clunk occurring between acceleration/deceleration or visa versa typically indicates a failing universal joint on a drive shaft. Take a look underneath at each universal joint while somebody shifts between drive and reverse. Watch for excessive movement in each joint. If you see one that moves more and/or has an audible "clunk" then that joint is failing. And of course safety is paramount, so the emergency brake should be set and the person in the driver's seat should be holding the regular brake when putting the van in and out of gear.
Regarding automatic transmission shifting.........I know from another thread you are having problems with your engine not running correctly (particularly idle changes and rough running associated with engine temperature). It should be noted that the shifting/performance of these older vacuum controlled automatic transmissions is affected by engine problems. Most of the time these problems go away when the root problem with the engine is corrected. Due to that I would recommend putting the transmission performance issue on the back burner until after you get the engine problem sorted out. Tim
Thanks Tim:
I replaced the drive shaft last year due to a hum I was getting from the yoke. It was doing this before I did the drive shaft, but very good point.
Your suggestion to hold off is a good one. I am a multitask kind of guy
There are so many issues with the van to accomplish and I am so busy at work I tend to be overly aggressive, as my wife says.
So yea, I will keep on the idle issue. In the mean time my power steering pump started making clanking noises. This is the third one since the rebuild but the other 2 just leaked. But I was smart enough to check with TVT and found your thread on the cavitation. Not sure yet on that, but what i am sure of is these idiots used power steering fluid and not ATF!!!
So guess what I am doing over the weekend. A set back for sure on the idle issue.
Thanks again, I am sure all of us appreciate your all the input you provide.
Older thread but my 1987 van has been having this issue for a few years now, but I also only use the van for road trips so it has been a low priority. Same issue as this started suddenly while I was on a road trip and only from 1st to 2nd shifting, so hours in 4th gear on the highway. It seems to be getting worse and I wonder if the rear end of tranny will explode as the shift from 1st to 2nd is SO violent. Otherwise the van runs great, starts every time, idles well, good mileage.... I've read over the other threads and it seems like I'll be dropping the tranny soon but was going to take a shot at rebuilding the valve body but am torn as it might make more sense to just pull the tranny and rebuild it rather than do some valve body work and spend money only to have drop the tranny later.
I guess I'm wondering what the resolution was to this thread
Other than the things previously mentioned here, you should take a look at your motor mounts. If you have a broken one the engine could be lifting and dropping on that side when you shift. Tim
Originally Posted by badartdog
Curious if this issue was ever diagnosed/fixed? Mine just started doing this too. Started super suddenly and now only does it between 1st and 2nd. '86 2wd Auto
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