[moontower69]

So after 30k hard miles, my 700R4's tv valve was sticking and not shifting out of first. Took it to local reputable transmission shop in Los Angeles and they said pump was failing due to aluminum impeller wearing out (and showed me little minuscule balls of metal being released).

I agreed to a total rebuild for $1600 bucks and upon picking it up, it vibrated like crazy (not driveline, did same in neutral). I'd seen this movie before and KNEW it was the converter. The shop has insisted on sending out my existing converter to be opened up and ensure no metal in it so they could warranty the rebuild for first of 24k miles or 2 years.

So I take it back and they get me a new converter and say the problem is that the converter hub sticks out about a quarter inch leading to a vibration - and blame the adapter plate. BUT IT DID NOT VIBRATE BEFORE THE REBUILD!

So they extended the snout on a new converter (w same 2000 stall) so it would go in far enough and claim that fixed the problem. I know that usually the washers/shims on the torque converter make sure that it compensates for the thickness of the adapter plate.

They swear they used the same washers.

I go to pick it up tomorrow and they say it's "much better" but still some vibration and if i'm still not happy, there's nothing else they can do. I'm a little worried I'm going to get stuck with vibrating converter again.

To me the problem is in their rebuild, but they CAN'T figure it out and I've already paid $1,600 bucks. Any thoughts on what could be wrong? The idea of lengthening the snout on a converter seems backwards to me and NOT fixing the real problem. Is it just stacked tolerances or they used the wrong bushings in the rebuild. Any help much appreciated!

[poncho447]

Well how did it go?

I have used at least a dozen of those adapter plates over the years with nary a problem, just shimmed the torque converter accordingly.

Used to have lots of vibration issues with the converter rebuilder we were using at the time, they had lots of excuses and it was always our fault. Switched rebuilders and end of problem.

[moontower69]

I'm picking it up on Saturday (I was waiting for some posts on PY to learn more).

I'm preparing myself for it to still vibrate - which means the rebuild is screwed and they won't stand behind it. I should've driven it before I paid.

I just can't believe they're blaming the adapter plate. Plus they forced me (and charged me $250) to send my perfectly good converter to "their guy" and it comes back vibrating.

My wife is gonna take me tomorrow, if it still vibrates I won't take the car back, that's my only leverage.

Any thoughts on the bull of them having to "extend" the converter snout 1/4"? I found this diagram online which shows the proper clearance between flex plate and tranny.

https://transmissioncenter.net/shop/...-instructions/

[Overkillphil]

Their thinking on the snout seems to be that the gap produced by the adaptor is not allowing the convertor to self-center with the crankshaft centerline. So that when the convertor is bolted to the flexpkate, it may be wobbling as you are relying completely on the 3 bolts for precision alignment which isn't their role.

Given the issues you've had, I have my doubts about the degree of influence that has on what you've experienced. It could be a bit of both, that is the snout not centering itself in the crank and a poorly balanced convertor with the latter being the major contributor. But as you pointed out several times, your original unit was perfectly fine for many miles.

At this point, if I were you I'd weigh the options of having them do the snout extension (call their bluff) at their expense OR just cut your losses and buy a good convertor from a known source and swap it out yourself (or take it somewhere else to have it swapped if you're not up to the task).

[FrankieT/A]

I would think if it were a converter problem it would vibrate in Park at whatever the RPM it is when it vibrates while driving If its a pilot issue. Maybe when they pulled the tranny they did something to bend the flexplate? Like either didn't unbolt the torque converter before pulling...or left one bolt in inadvertently while pulling? I would have them run the car on the lift with the inspection cover off and look for wobble. Which would soon wipe out the torque converter bushing and seal.
THIS IS WHY I HATE DEALING WITH TRANSMISSION SHOPS!!!! No offense to those very few tranny shops that know what they're doing.

[Blued and Painted]

I had a bad converter that vibrated like a skip at low RPM and Hi load. More pronounced in reverse. TH350
I chased the aparent ignition problem for months. Finaly the trans overheated and failed. So a trans overhaul by Luke Duke with a new converter. Bingo, perceived skip was fixed. 2 cents.

[n2ogpsj462]

Very few good tranny shops? You should say the few that give others, like mine, a bad name. They either bent your flywheel or bad converter. Did I understand correctly that 2 converters had the same vibration or they cut the first new one open to check?

["QUICK-SILVER"]

Originally Posted by moontower69

Any thoughts on the bull of them having to "extend" the converter snout 1/4"?

My thoughts are with Overkillphil on this. Cenetring knob isn't fitting in the back of the crank as it should. The adapter plate plus whatever washers/shims that are needed, between flexplate and converter, has the centering knob out of the crank.

I'ld think that adapter plates should come with somekind of ring to extend the centering knob.

Getting a good balance without it (depending on just the bolts) would've been pure luck.

Has to be what their extension is suppose to cure

Clay.

[moontower69]

Thanks everyone. I did call their bluff, they've put in a new converter with a 1/4" longer snout and say that helps it (I'm skeptical). I pick it up Monday.

If it vibrates, I will ask them to disconnect converter bolts and show that vibration is gone. I'll also look for a warped flex plate.

So in summary, if it still vibrates either:

1. flex plate bent when they removed tranny
2. failure to properly shim the converter (and get balancing hub far enough in)
3. converter is bad
4. read that sometimes paint or damage to hub on converter can keep it from seating properly?

Monday is the DAY. If it still vibrates, I'll ask to see it run with dust cover off - and see if flex plate wobbles or converter hub wobbles.

If vibrates, I'll ask for a $250 credit I paid for them to open up my old converter (although I'm still OUT a perfectly good converter). I have a converter from Edge that I'll have them put in and see if that fixes it. He said he won't swap another converter but that's only fair if it still vibrates.

[n2ogpsj462]

First off its crazy they charged you an additional 250 to pull it back out to check the converter unless it was YOUR used or new one that was the suspected culprit however I couldn't imagine a shop that would reuse the old converter with 'minuscule metal balls in the pan'. Second the only way they could've bent the flywheel would be if they had a hack installer who put his pry bar between the converter and flex plate I order to separate and still would require some pretty rusty dowels and heavy prying to actually bend it. Like I said before my guess is the converter which I've seen numerous times until we switched to a better converter company. If unbolting the converter and sliding it back cures your issue then you know what your issue is but make sure it gets pushed all the way back into the pump.. I've also seen company's put so much paint on the converters that they need to be pryed into the crank pilot. We always scotch brite and grease the hub

[TedRamAirII]

After your inspection and if these geniuses cant figure it out, and I suspect its their own doing. I would tell them either they can FIX it correctly, or they can sublet it to a real trans shop to FIX it correctly, or refund ALL your money so you can get it FIXED. Ask the owner nicely which option they want to pursue, and then be quiet, and see what answer they give you. That will determine the integrity of this place.

[moontower69]

Okay, I got it back from the transmission shop this morning and....the vibration is gone. They said the 1/4" snout extension worked (don't know). I know that I don't love "fixes" for problems that aren't there. I think they lost the shims from my old converter and tried to use some thicker washers off the shelf.

When I asked why/how converter would need to be 1/4 " closer to flex plate to solve an imbalance, they said the "geometry" of the motor shifted forward when they removed the tranny for rebuild and had to compensate for my adapter plate. Yeah, I think I've heard it all now.

But, I got my car back to where it was (they didn't give me my $250 back because said my old converter needed to be opened up to ensure no debris and validate their warranty).

FINE. In the end, it was a hassle but they made it right and she's shifting nice and strong - and no more uncontrollable high revving shifts (or sticking in first) to attract police attention.

Thanks again everyone for the info, it helped me get them to right the wrong.

IN the end, the converter company they use probably SUCKS. They probably destroyed my old converter (or too lazy to pry it apart) and gave me a recycled converter w/ a damaged balancing hub which caused the imbalance.

[Me Notyou]

That sucks. You should start a yelp account and make sure you give them a bad review. "The motor geometry changed "? WTF LOL !!!!!!!!!!!!!!!!!!! Maybe the crankshaft came out of round when the flux capacitor ran out of blinker fluid... That would explain the vibration. That or the grade 8 bolts were too hard, and they gave you grade 2 sheet metal screws at a discounted price. You know, they're softer so they absorb impact better.... ?

[n2ogpsj462]

I've used the jegs adapter plate on my own 700 with the supplied shims and changed converters numerous times in the 8+ yrs since I did it plus a dozen or so swaps for guys. Glad it's fixed but likely not getting a truthful story

[TedRamAirII]

I can appreciate them wanting your old converter cleaned because of debris (thats like you wanting to put a old oil filter off a scattered engine on your newly rebuilt engine) But nothing should change any "geometry". They lost something and didnt get you converter installed properly. I just hope there isnt any long term damage. Do you see any new parts at the converter? I sure would look it over good.
Glad its back rolling. ; )

[Overkillphil]

"Gee I'm a tree"

[Blued and Painted]

Originally Posted by TedRamAirII

(thats like you wanting to pull an old oil filter off a scattered engine and installing it on your newly rebuilt engine)

Seen it done by the new guy at the dealership. Yes, a new short block was lost