How do I know if my torque converter is bad?

[Kiqman]

Is there a simple test or do I have to pull the tranny to know if there's anything wrong with the torque converter? Feels like my tranny is slipping but the fluid looks a nice red.

 

[onetonbb74]

will it hold any gear or will it slip in and out while driving? Also, pull the cover on the tranny bellhousing, start up motor and see if the torque convertor is walking or out of round. It should be a perfect spinning circle.

 

[Kiqman]

It only seems to slip when I put it under a lot of load and my speed is under 30 mph. It's not like it in neutral - just not as torquy at the rear wheels as how the engine sounds. It is a built motor so I thought maybe the stock torque converter was too weak? I forgot all about the cover on the bellhousing. Shows how long it's been since I pulled a tranny.

 

[1985_K5_Silverado]

It only seems to slip when I put it under a lot of load and my speed is under 30 mph. It's not like it in neutral - just not as torquy at the rear wheels as how the engine sounds. It is a built motor so I thought maybe the stock torque converter was too weak? I forgot all about the cover on the bellhousing. Shows how long it's been since I pulled a tranny.

Will it slip under heavy load in any forward gear, or just in some gears? Have you done a line pressure check on the tranny? What model of tranny is it?

 

[RustBuket]

It only seems to slip when I put it under a lot of load and my speed is under 30 mph. It's not like it in neutral - just not as torquy at the rear wheels as how the engine sounds. It is a built motor so I thought maybe the stock torque converter was too weak? I forgot all about the cover on the bellhousing. Shows how long it's been since I pulled a tranny.

Sounds like your tranny is slipping.... Check to see if your tranny fluid smells burnt and is blackened. If so, there isn't much time left. Your built motor is probably what killed it.

 

[francis]

have you serviced it? most people service there trans at the first sign of anything funny. and what that does is clean all your seals and sealing surfaces and it takes just enough varnish and buildup off to make to much clearance and then it makes the sliping really bad and then you smoke the trans but anyway to answer your question, no there is no way you can do anything to a tc accept to cut the weld open and look inside and then weld it back up. but you have to have the right equipment to do that. yes you can look inside were the input shaft goes but that is not were the tc does all it's work. the splines are all you'll see and if they strip you would either hear it ( sounds like power steering but from under the truck)or you'll quit pulling altogether. it sounds to me like you have a stuck valve though. is it down shifting when you stomp on it? if you serviced it you could have gotten some trach in it. it only takes one grain of sand to stick a valve. get some lucas trans fix the stuff works wonders. you may think "oh thats just patchin' it. I don't do that" give it a shot I could go on and on but it works like nothing i have ever seen (not that I've seen much)

 

[R72K5]

hum i wonder about this

because in my 77 th350 it doesnt smell burnt at all but it doesnt seme to get all the wayinto third gear like it shoul, isnt holding it as well as it should be

and the PO said they had it rebuilt a coupel years ago and its painted blue and the torque converter is painted black, not original black metal one

what do you think ?


hmm

thanks

 

[Kiqman]

It's the 700r4 with OD.

Will it slip under heavy load in any forward gear, or just in some gears? Have you done a line pressure check on the tranny? What model of tranny is it?

It seems to slip under load in any gear. It kicks down fine and builds speed while shifting smoothly. It just seems like when I get on it a little (I don't stomp on it ever) there's a little power lost - almost like I'm slowly letting out the clutch - but it's an automatic.

 

[1985_K5_Silverado]

It seems to slip under load in any gear. It kicks down fine and builds speed while shifting smoothly. It just seems like when I get on it a little (I don't stomp on it ever) there's a little power lost - almost like I'm slowly letting out the clutch - but it's an automatic.

If you aren't making sufficient line (fluid) pressure (perhaps from the front pump goiung bad), it can let the clutches slip and give you the same feeling you get with a manual when the clutch slips under load, and the clutches will grind themselves to a gritty paste in your pan.

Unfortunately, most auto trans vehicles don't have a trans line pressure gauge, or even a fluid temp gauge (though this one is far more likely to be added aftermarket than is a line pressure gauge), so the only way to check it it to screw a hose and gauge into the pressure tap and test it that way.

It's a 700R4, is that right?

 

[Col_Sanders]

If you aren't making sufficient line (fluid) pressure (perhaps from the front pump goiung bad), it can let the clutches slip and give you the same feeling you get with a manual when the clutch slips under load, and the clutches will grind themselves to a gritty paste in your pan.

Unfortunately, most auto trans vehicles don't have a trans line pressure gauge, or even a fluid temp gauge (though this one is far more likely to be added aftermarket than is a line pressure gauge), so the only way to check it it to screw a hose and gauge into the pressure tap and test it that way.

It's a 700R4, is that right?

What should my pressures be? Installed a level 2 tranny from bowtie overdrives and the shift from 1-2 is good, but the 2-3 is weak (according to tranny shop). Checked the pressures at idle and came up with ~85 or so at idle and went down as I change the gears.