Sonnax zip kits

Anyone have experience with the above? Considering it as a “while it’s out of the car” maintenance item for my trans valve body; looking for reviews.

In addition, if anyone has experience with Sonnax’s valve body pressure tester and can tell me why it’s worth $300 for what looks like could be done with a $5 piece of acrylic, a drill press and an air hose fitting, I’m curious as well. (Full disclosure, though: already bought the $5 piece of acrylic)

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This thing?

That’s the one.

I guess the magic’s in the “sealing pad”…
I have to be pedantic and ask: you’re aware it’s a vacuum tester, right? (Which one can make a solid argument is really just a pressure tester for atmospheric pressure, but…)
The big thing, in my mind, is having to have a vacuum source. A decent pump (to meet their 3cfm requirement) is going to cost a decent bit. I think even Harbor Freights sees $200 or so for theirs…

It’s not pedantic; it’s covering all your bases!

Vacuum = pressure + venturi generator
Or put more simply: given a source of compressed air, knock a zero off your estimate… https://www.harborfreight.com/air-vacuum-pump-with-r134a-and-r12-connectors-96677.html

Not that I’ve ever bought one of those – too easy to make your own. CFM is then bound only by your compressor and the diameter of your tubing.

That said: Sonnax would have to convince me that 3 CFM is a realistic requirement for this task (as opposed to it being, say, the cheapest vacuum pump they could find and resell, probably similar to https://www.harborfreight.com/25-cfm-vacuum-pump-98076.html at only 0.5CFM less).

1 ft3 = 1728 in3
3 CFM = 0.05 ft3/s = ±86 in3/s

I’m pretty sure I can find some way to tell if a 1/2" valve bore is leaking out of tolerance using less than 86 cubic inches of air per second.

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I used their kit in my Excursion. If you are doing anything to your valve body, I would highly suggest you get their valve bore sizers. They don’t sell them with the kit normally. A local source for that stuff is TranStar down off Irving Blvd. You may be better off if you got a replacement valve body & add the kit to it. Then you wouldn’t likely have to mess with the valve bore sizing.

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While it’s true those Venturi devices work well for HVAC evacuation, I’d be hesitant to use one here for the noise factor (if I’m looking for air leaks, I like to hear them), but having never tried it, might work just fine and my reasoning may be unsound, given that you’re looking to get gauge readings anyway (also, I can think of several ways around that, and I’ll bet you can, too).
I’d love to hear your results if/when you try whatever you try!

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You may be better off if you got a replacement valve body & add the kit to it. Then you wouldn’t likely have to mess with the valve bore sizing.

You think? I was hoping that I’d find most of the “durables” in the valve body okay, and would mainly be replacing the “easy stuff” from the zip kit after pressure testing and ideally not having to re-bore at all – gotten pretty lucky so far wrt this tranny’s condition, but then again, it does have 125k miles on it of unknown treatment (and no fluid change for the first 105k of that)… I may be being overly optimistic. Hmm. Valve body’s officially coming off today, so we’ll see how it looks, I guess!

given that you’re looking to get gauge readings anyway

Yeah – I’m by no means a hardcore trans valve body expert, but AFA I understand it there is always leakage at pressure with those, by design, which complicates “by ear” diags. Gotta go with gauge readings. Thinking I’m best off doing it “leakdown” style, using a second gauge as a differential reading and tacking on a little math at the end there. :slight_smile: We’ll see if that works, I guess…

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The thing about valve body’s is that the motion of the valves around will create a build up of material. This build up is what causes them to stick, amongst other items as well. I resized my factory VB & still had stiction happen even though dry it was ok. The thought was the tolerances were still too close in spots & when the valve body heated up the valve body would then expand causing said stiction.

This may be a dumb question, but wouldn’t the sleeves and housing expand more than the valves themselves – and since the valves are anodized, wouldn’t the anodic coating crack before you got any significant expansion to those valves?

Sonnax had me pretty worried about sticking already, honestly, but for different reasons: https://www.sonnax.com/tech_resources/114-valve-body-bore-preparation seems like about a dozen bazillion things that could go wrong :slight_smile: just gonna have to keep fingers crossed and see how it goes, I guess; current budget won’t look too kindly on buying an entire backup valve body. Still got some time to plan this out; valve body removal’s been postponed to either tomorrow or Wednesday (because life happens, it turns out), and I won’t have the zip kit in my hands before Wednesday at the earliest anyway, more likely Friday.

Well, my wishful thinking may become less wishful soon. I sent an oil sample to Blackstone when I started pulling bits off of it; just got that back – signs of wear well above average to steel and brass… again, definitely not a valve body expert, but it stands to reason to me that if you’ve got significant wear to anything in the gearbox/bell housing it’s probably due to things getting loose and sloppy in the valve body first.

Oh, well. Zip kit just arrived and is waiting for me at home, and the valve body is in my trunk… I’ll probably swing by DMS some time tonight and see how bad it all looks.

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…did I say tonight? I meant Friday night. Life’s a real sonofagun sometimes.

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So, just a follow-up:

Wild success. Car shifts better than it has the entire time I’ve owned it. Still need to look at the hard parts of the transmission at some point, since I know one of the clutches is leaking like a sieve – but it still drives pretty great. Gotta fix two more problems and then I’m back to having a daily driver.

(EDIT: now only one more problem. Had a cylinder misfire code – it was a lightly fouled sparkplug, that also felt overtorqued. Short-term fix of cleaning up the plug was therefore super easy, and it clears the CEL so I can get the thing inspected. Last thing is replacing the alternator so I can drive it longer than 5 minutes without it dying; if anybody has a good source of a salvage 180A unit for under $100 let me know…) :wink:

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Glad to hear the valve body work was a success!

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