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New Transmission revs after 2nd gear. R, 1st, 2nd work, after that it just revs.

6K views 18 replies 4 participants last post by  Ravalli Surfer 
#1 ·
Hello there,

I just got through swapping out my transmission in my 2003 Chevy Trailblazer LT 4.6 4x4 Auto with 179k. Bought this new trans off Ebay from Detroit Axle. It came preloaded with a torque converter. It worked okay for a day or so and now I have nothing past 2nd gear. Full power through 1st and 2nd. D and Manually shifting is the same outcome. If my pump was bad, it wouldn't go anywhere, right? Its not leaking, fluid is good, no engine codes. When I do go into third or D, and let off the gas, I watch the RPMs and it moves as if its shifting through the other higher gears, but when you go to hit the gas it just revs, unless I manually shift it back into 2nd. I am pretty pissed I just spent all this time putting this thing in and now this.

I emailed the seller, of course no response yet.

Maybe solenoids? Anybody else run into this? the posts I seem to click on never seem to come to a conclusion, just other people asking for a resolution lol.

Thanks!
 
#2 ·
Does the speedometer work? That's important.....
Might be a blown forward sprag..... but ...... your symptoms might be understandable with an old, many miles transmission - because then I'd say that the “3-4” clutches are worn out.

How did the old unit die?
  • Did you replace or 'clean out' the transmission cooler and lines?
  • Heat exchangers never really come clean no matter how good you clean it - replacement is the only way to guaranty a clean job.
  • You might have some metalled-up solenoids and metal shards in their rare earth magnets if you didn't get a fresh heat exchanger in the radiator (a new radiator is better though).
  • If yes to any of that - the EPC might be stuck and/or you've re-metalled out the new unit.
Either way - and if I'm right - pull it out and get another one. before they say you abused it.
 
#3 ·
I flushed the cooler until it was fresh fluid through the entire system. The speedometer works.

The old one isn't fully dead, it just needs a rebuild because it was forcefully driven with a clogged catalytic converter for many months.
I cut the cat off which fixed my issue with it not going over 4500rpms.

The new one shifts into 3rd and drive, but doesn't go anywhere. If I am lucky, going downhill, I will manually shift it from 2nd to 3rd, I watch the Rpms go into 3rd. I'll coast then tap the gas slightly and it will lerch like it starts to go in 3rd but then just revs out like it's in neutral.
 
#4 ·
Hmmmmmmmmmmmmmmmmmmmmmmmm ..... I'm leaning toward the busted sprag ................ but the builder might have nicked one of the piston seals on the 3/4 clutch pack. .

What did you find in the cooler and the lines when you cleaned/blew them out?

Was the original pan full of metal?
 
#5 ·
UPDATE**** Went and grabbed a 2-3 shift solenoid and a new filter/gasket and fluid. Dropped the pan on the "new/rebuilt" trans to find there was NO FILTER installed from the seller.... trans burned itself right up. They shipped me out another transmission, dude on the phone says he was going to specifically confirm and make sure there is a filter in the next trans....

2nd new trans arrived... got it up into position, dropped the pan just for fun, and BAM, no trans filter AGAIN! I put a filter in it, filled it up, and it drives OK. 1-2nd doesn't shift properly unless you floor it above 4500rpms, or you barely hit the gas enough to feel it shift. If you drive it normal, you definitely can tell it doesn't like 1-2 and 2-3 unless you are getting on it. NOW the trans shop says I need to check my TBS voltage to see if its sending the proper signals to the trans for the proper pressure....

Good news is, I can change a trans out in one of these pretty quick now... lol
 
#6 ·
With a record of leaving out the filter teice... I wonder how poor in quality the unit is anyway.

There are so many ways to screw up a transmission that I'd have to be psychic to even have an idea.

Mismatched parts are a real primary problem.... they lend to oddball shift patterns and missed or stacked shifts and no matter what you do you'll never correct some problems without a complete teardown and full evaluation on what the bench monkey did to the unit.

I don't hold out much hope for you solving this problem.... maybe .... but not likely.
 
#7 ·
03 T-Blazer LT, look at this:


Hopefully you can get your money back and get another transmission from a reliable rebuilder.

Good luck!
 
#8 ·
I'm very glad I saw this post on "Detroit Axle"! I WAS looking at their "complete front end rebuild kit" with upper and lower A-arms, ball joints, struts and wheel hubs, but I won't risk dealing with them because they can't even bother with putting filters in their "remaned" transmissions. If their other products are as shoddy as these transmissions were, I'm not doing business with them! "03T-BlazerLT", good luck on getting them to return your money so you can get a better transmission from a better refurbisher!
 
#10 ·
They're pretty much a different company - at least they appear to be so in name only as a warehouse. I know that I built transmissions for Ford, Subaru and even Saturn, and they all refereed to their parts as "Theirs" when they wee mine that I built under license.
 
#9 ·
I prefer to purchase parts from a known manufacturer as opposed to purchasing a house brand part priced way, way below the known competition. I know I might be paying more for what might be the same part, but then again I might not be buying a low quality part of unknown origin. I guess the only exception to this are the professional grade house parts from NAPA or Carquest which typically come from the likes of Moog, Fel-Pro, SKF, Timken, Standard Motor Products, Dana, Spicer, etc.
 
#14 ·
Luckily, we have a local trans company that has been in business 30+ years that does a great job and stands behind their work. They'll either reman a trans you bring to them, OR even pull remove/re-install, if the customer prefers. They replace ALL "Soft parts", supply a NEW torque converter and upgrade any hard parts necessary on ALL their builds to bring the trans up to or surpass the latest specs. They will even do a "super firm" shift kit for people who race automatic corvettes/camaros. I had one built that would light the tires when it shifted from first to second for my "toy" '98 silverado "shortie" and it was less than 2 grand including remove/reinstall ,upgraded computer shift points and two year warranty. Not a bad price for a 500hp set-up!
 
#17 ·
Ravalli, only partial accolades from me towards NAPA. I shy away from their relabeled Dorman parts unless I absolutely positively have no other choice. I was thinking mainly about their parts they source from Gates, Standard Motor Products, Raybestos, SKF, Dana/Spicer, Mahle, etc. Regardless of the brand, one has to be really careful these days when they are buying parts. Unfortunately with all this global manufacturing and the MBAs trying to squeeze out as many pennies of profit they can, it's tough to find any singe brand one can count on for quality parts all the time.
 
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#19 ·
Time for another "7 Month Late Reply" ........

In the Olden Days, there was a terrific purveyor of parts called "TRW" in that they reboxed everything in their own boxes.... sometimes they'd just open up the original box (Phikco, Sorensen, Ford, GM, Mopar, etc) and inverted it, stapled it back together inside out and stuck their label on it and called it TRW.

NAPA has been doing that but using vastly inferior Oriental (hint, hint) parts under their "house line".

Ever seen a 10mm head on a 1/4x20 bolt? NAPA has them.

As it is, I'd like to find some TRW parts again. I think we are seeing the death of the auto parts business.

New Federal regs delete manufacturers needing to produce OEM parts for 36 months ... not the old seven year moratorium as it stands now.

I remember when the standard was 21 years ... but with the genesis of so many models and permutations of models, stocking parts became too invasive to the dealership footprint ... so I can see the reasoning .. albeit begrudgingly.... to maximize square footage returns for real estate investments and property tax bases v fiscal returns.

Yup ... the parts business as known currently ... is spiraling around the ol' drain hole.

Aftermarket parts, proscriptive gun laws, Boomers in diminishing supply, Covid, face masks, melting icebergs, penguins and polar bears in Miami, cats and dogs sleeping together, a derth of singing fat ladies .... it's making sense now.
 
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