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All gears act like neutral

951 Views 27 Replies 7 Participants Last post by  miketx
I'm getting on the interstate in 2nd gear and I get on it just a little bit and then it starts to rev up so I let off and put it a 3rd and I started driving and it was fine, I was out with friends and didn't mess around the rest of the night and then picked up someone else told him it happened put it in 2nd did a couple 20-40 pulls to show him what I did and on the 3rd pull, all gears went into neutral including reverse tranny fluid is very light redish brown but no leaks anywhere. I can't tell if it's low or not what would be the problem? It also does not go into gear. It has around 4-5k miles on it rebuilt with hd2 trango kit shift kit
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If bad pump, you can hook up a line gauge and check pressure. There is a hook up for that.
Any codes shown for the trans?
At minimum get a sonnax boost valve in the pump they are cheap and take no time to put in. Also get a new drum and a wide band clutch installed.

There is more preventatives that can be done in the valvebody, but from your two immediate failures, those two things are worth swapping
What is a wide band clutch?
Similar to this. Vs the stock band which is around 2.2" wide. Usually an alto red or this raybestos black or borg Warner are what to get. There are different clutch types and carbon ones are often not for street vehicles

Again you need a new drum for this too to match
Ok, you mean a wide band. Got it. Wonder how that works? You can't make the drum any wider.
More surface area on the drum... The stock sized band has lots of room to be larger. This is why this part exists. It's only dollars more than the OE sized one that it's a no brainer. You should as a best practice replace that drum too with any build to ensure flatness. So for a few dollars more why not?

Though this is often not the M.O of many cheap Trans shops.
Correct. It's only 0.2" larger but now applies to near all of the drum.

Of course check play and you might need a new pin and then have to adjust from there too. Don't follow the atsg manual for specs. Basically divide their recommended specs by about half. Then you're in the ball park for proper clearances
I just check the drum with a straight edge. If it's flat, it's flat.
If you stuck with the oem sized band I probably wouldn't argue with you there. But if you change to the wide band, that's a no no. I hear you can put them on a lathe though and some shops will do that. But there isn't a stated minimum thickness spec I can find otherwise.
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What pin are you referring to? What's wrong with the atsg manual? Clearances for what?
The 3/4 clutch pack clearances and the wideband/pin engagement clearances are way looser than it should be as stated.

The secret sauce the performance trans builders often don't mention it, but if you pay attention, you'll find its way tighter. As an example performabuilt will do the 3/4 clutch pack at like .019 or something like that but the spec calls for around .07. Many builders settle in for around 0.03.
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Thanks, have you rebuilt a lot of them?
Only my own, twice. Dozens of hours on YouTube, and asking a lot of questions in various fb groups.

I really want to learn valvebody vacuum testing but don't want to buy the tools for it.
It's rare for a VB to be bad. I've seen very few that were actually bad. A good cleaning, including removing some of the valves to clean properly and then running a flat file over the VB assy will fix it up 99 percent of the time.
If you were to believe Sonnax, they market their parts as if they leak like a sieve. 😛
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