TH400 help!
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On The Tree
Joined: May 2014
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TH400 help! I have a th400 the builders first shot was a crossleak issue, their next shot was the pump failed (very slow to shift between all gears, and lots more rpms to get it to move). I cleaned out my reverse manual valve body best I could and swapped it over to a spare th400 I have.
I bolted everything up and it seems to shift and run fine except for third gear. I shift to third and the output immediately stops...I give it gas and it acts like it is bound. What would be your best guess? My plan is to get an FTI transmission anyways, but need a transmission to diagnose some other issues.
This is what was in the first transmission
The left tube was from the original K30 deep pan equipped TH400, the right one is out of my buggy that they did with the deep pan as well. Not the right tube, not the right bolt, not even close to the right spacer.
I bolted everything up and it seems to shift and run fine except for third gear. I shift to third and the output immediately stops...I give it gas and it acts like it is bound. What would be your best guess? My plan is to get an FTI transmission anyways, but need a transmission to diagnose some other issues.
This is what was in the first transmission
The left tube was from the original K30 deep pan equipped TH400, the right one is out of my buggy that they did with the deep pan as well. Not the right tube, not the right bolt, not even close to the right spacer.
Thread Starter
On The Tree
Joined: May 2014
Posts: 109
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My friends old K30, tag looks like it says 87 but I thought that was the changeover year.
Valve body was off my original TH400 the one full of metal...its a Hughes Full Manual Reverse.
Yeah spare 400, I don't care if this one dies either, still have 3 or 4 more. Going FTI 4.5 anyways, but I would like to get rid of a couple little things before that.
Valve body was off my original TH400 the one full of metal...its a Hughes Full Manual Reverse.
Yeah spare 400, I don't care if this one dies either, still have 3 or 4 more. Going FTI 4.5 anyways, but I would like to get rid of a couple little things before that.
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It was phased out around 1990.
There are minor differences in the valve body for 1987 and 1988.
A bind up in 3rd could be a check ball in the wrong place or a mismatch in the valve body.
I have a feeling no matter what I say you're going to say you already covered it. Maybe try one of your other cores. Since you're taking the valve body out why not check the internals? A 400 is so easy it can be done in not even an hour.
There are minor differences in the valve body for 1987 and 1988.
A bind up in 3rd could be a check ball in the wrong place or a mismatch in the valve body.
I have a feeling no matter what I say you're going to say you already covered it. Maybe try one of your other cores. Since you're taking the valve body out why not check the internals? A 400 is so easy it can be done in not even an hour.
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On The Tree
Joined: May 2014
Posts: 109
Likes: 1
I didn't put in any check ***** since there were none in my original transmission build.
No I appreciate the help, automatics are new to me. They are easier to take apart than I expected, a couple snap rings I was surprised.
There are so many unknowns in this current transmission that I am just going to start over....although I pulled a couple trees out of my pond and drove it around a bit...shifts and drives perfect...minus 3rd gear of course.
No I appreciate the help, automatics are new to me. They are easier to take apart than I expected, a couple snap rings I was surprised.
There are so many unknowns in this current transmission that I am just going to start over....although I pulled a couple trees out of my pond and drove it around a bit...shifts and drives perfect...minus 3rd gear of course.
Here are the instructions, not sure if skipping any of these steps would cause the problem your having.
http://static.summitracing.com/globa...up-hp2211r.pdf
Thats all I can think of. Have fun, hope you get it figured out. https://ls1tech.com/forums/attachmen...1&d=1465093648
http://static.summitracing.com/globa...up-hp2211r.pdf
Thats all I can think of. Have fun, hope you get it figured out. https://ls1tech.com/forums/attachmen...1&d=1465093648
Last edited by Jays_SSZ28; Jan 30, 2018 at 07:58 PM.