Tranny issues
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Tranny issues I had a probuilt transmission kit done to my tranny. At first I thought all was well but the more I payed attention the more I started noticing little issues. I noticed that going from N to D I get a hard push for some reason. Also the shifts were very soft. You actually had to be paying attention to even know it shifted. And last but not least there are times when the car will not shift from first gear.
We traced that to the vacuum hose in the T. For some reason it bends and prevents it from shifting I guess. First thing we did was get a new seperator plate and re-drill smaller holes. Then we installed high performance Superior intermediate billet servo, a high performance Superior overdrive billet servo and that's when everything went bad.
On the first test drive the car felt like it had no power and it shifted 1000 rpm's earlier than it did before. Also the shifts became softer. Now were going back to the servos that came with the probuilt kit but I still dont know what to do about the horribly soft shifts. Any input would be great because Im this close to giving up on this POS.
We traced that to the vacuum hose in the T. For some reason it bends and prevents it from shifting I guess. First thing we did was get a new seperator plate and re-drill smaller holes. Then we installed high performance Superior intermediate billet servo, a high performance Superior overdrive billet servo and that's when everything went bad.
On the first test drive the car felt like it had no power and it shifted 1000 rpm's earlier than it did before. Also the shifts became softer. Now were going back to the servos that came with the probuilt kit but I still dont know what to do about the horribly soft shifts. Any input would be great because Im this close to giving up on this POS.
So you had a kit done such as rebuild kit?
Who put that in? Was everything air tested? what did the 3-4 clearance end up at? what did the band clearance end up at? what did a line pressure check reveal? What year is the transmission?
Did you do a converter at the same time?
Who put that in? Was everything air tested? what did the 3-4 clearance end up at? what did the band clearance end up at? what did a line pressure check reveal? What year is the transmission?
Did you do a converter at the same time?
soft shifts = low pressure, check your line pressure....tell your guy to get back to basics I think you can salvage this ...but like 8a8mfh has stated you've gotta check a few things, and know what these clearances are.... get rid of that small hose(vacuum hose ) an get a good quality 1/4 inch air/hyd. hose(something that will not bend), or steel tubing for your vacuum supply line, trapped vacume will give you the results you have discribed... while your at it dissconect the vacuum supply it'll go to full line ..Thats an easy check...Hope this helpd ..Dave
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From: The beautiful Kingdom of Bahrain
Originally Posted by 8a8mfh
So you had a kit done such as rebuild kit?
Who put that in? Was everything air tested? what did the 3-4 clearance end up at? what did the band clearance end up at? what did a line pressure check reveal? What year is the transmission?
Did you do a converter at the same time?
Who put that in? Was everything air tested? what did the 3-4 clearance end up at? what did the band clearance end up at? what did a line pressure check reveal? What year is the transmission?
Did you do a converter at the same time?
Originally Posted by Honda Hunter
The 3-4 pack clearance was 0.03", the band clearance was about 0.12". It's a 1994 tranny. We have no way of checking the pressure. How does one adjust the vacuum modulator?
Did you call and get these numbers for the clearances? Sounds like the generic "this is what they should be so tell him that" answer.
You don't adjust the modulator on a 4L60E, there is a screw in the nipple but thats not to be touched. During assembly any adjustments are made by grinding the pin size.
Never installed my vac mod kit but the higher the stall speed the shorter the pin, I would assume the pin was installed as is and needs to be shortened.
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Reduceing the pin lenght reduces the pressure.....try removing the hose thereby putting it @ 0 vacuum, read the pressure..... you should get max line...no more than 230 max in drive....you'll need a gage that will show 0-400 psi....I wouldn't touch the pin till you get a reading on the line pressure....hope this helps Dave
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If you remove the vacuum line at the "T" it'll throw the trans into HI line...and it will shift after that...you'll have max pressure....You'll need a hyd. pressure gage that goes from 0-400 psi....hope this helps Dave.... (nice pic of the service port)
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From: The beautiful Kingdom of Bahrain
Originally Posted by Rock-On
If you remove the vacuum line at the "T" it'll throw the trans into HI line...and it will shift after that...you'll have max pressure....You'll need a hyd. pressure gage that goes from 0-400 psi....hope this helps Dave.... (nice pic of the service port)
Hey , When your hose kinks, theres a chance that it will trap low vacuum below the kink, therefore because of the kink, it will not allow the modulator to go to full line...or 0 vacuum, ergo the soft long low pressure shifts. Pressures should read say 90 psi @ idle, to 230 wot in drive, and 140 idle to 300 wot in reverse, or there abouts , also becareful and make sure line pressure matchs foot travel(in other words the pressure has to snap up and down, matching foot travel)...hope this helps Dave
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From: The beautiful Kingdom of Bahrain
Good ifo, thanks. Right now my TPS sensor is giving me issues so I must replace it and see if it shifts normal. I need to find something fast to check the line pressure.
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Got it all figured out. Replaced the hose, and tps sensor and it seemed to work out. Shifts still arent neck snapping but screw it, it shifts and that's all that matter. My next and final question is what's the difference between the stock seperator plate and the Transgo seperator plate ? When we replaced mine we used a stock one and redrilled the holes. Should we have used a transgo seperator plate? Thanks everyone for all the help. On a side note, I noticed with old hose whenever it kinked the trans temp would shoot to 195 easy is there a reason for this?
With the hose kinked, there is a good chance that there was trapped vaccum in the line. This would will translate into low line pressures because the modulator is "seeing" vaccum. Not a problem when at lower throttle settings but when you apply power and the vaccum mod has set low line pressure you will have some slipping clutches, which in turn creates heat and heats the fluid. Then you see the result as increased fluid temp. Glad you got the issues worked out.
Mec
Mec
what's the difference between the stock seperator plate and the Transgo seperator plate ?