DC-1000/2000 Improvements

Torque Converter Rebuilders Association

June 2008Issue 9, Volume 6

[email protected]

PLATINUM SPONSORS: Monthly publication of TCRA newsletter provided by Melissa Hall of Melyns Print & Pro.

TransmissionCertified

Taking A Closer Look...DC-1000/2000

Overall Height7.625” to 7.640”

Internal Clearance

.015” to .017”

Application:2001 and newer GM Allison equipped trucks

Degree of rebuild difficulty:

Largest area of concern:

8

Hub run our under .005;clutch plate condition

Dacco Part NumberDC-1000/2000

The Allison 1000/2000 appeared in 2001 in many GM heavy duty trucks and later

model Fords. Several improvements have been made with a few positive results. As popularity increases, rebuilders need to be aware of the factory short comings and capitalize on known improvements. This is one converter that should not be rebuilt as a stock OEM design. Known early warning signs will tell the story. If impeller hub wear is even slight (2.293 is new, 2.2915 or smaller) the hub should be replaced. A pump failure or complete transmission failure could occur leading to

a costly comeback. Excessive clearance be-tween the hub and pump bushing can also lead to converter clutch malfunction. Nei-ther you nor your customer can afford this. Use only a new flanged hub. Do not try a butt mount hub here. There are many areas to inspect for prob-lems. First take a very close look at the damper springs. Early units used in GM diesels commonly are found with broken or weakened springs. Even later convert-

ers, as shown in photo A, need careful examination. They may be hard to see but the larger outer springs do break. If the converter has metal contamination, remove and clean the damper assembly. This is a hiding place for debris such as clutch material and metal particles. If the clutch lining is to be replaced consider using a stron-ger carbon type liner instead of the OEM design. Heat is a real factor here and the paper type clutch is not a good choice. They are usu-ally worn or burnt from excessive slippage. This brings us to the front cover. Hot spots indicate slip-page and possible distortion of the front cover. You have a choice of resurfac-ing the clutch contact surface after careful inspection for cracking near the mounting pad area or replacing the cover with a new one piece billet. This is the preferred choice among rebuilders. It provides a stronger converter to flywheel mounting area that will not crack along with a clutch contact area that will retain integrity from friction and heat under severe use. The newer units have better bearing than the 2001-2005 models. Shown in photo B is the latest improvement. Early converters should always have the bearing replaced. Testing them and inspection efforts will certainly lead to regrets. Replace them now and avoid a comeback. As a last notation, inspect the outer most ring of dimples located on the impeller. Small nicks or indentations of the dimples can cause engine and or transmission mal-function do to erratic magnetic impulses

DC-1000/2000 Improvements

from the speed sensor. Properly rebuilt, this converter can add to your company an in-creased profit center.

Dennis SneathMidwest Converters

Rockford, Illinois

Photo A

Photo B

Photo C

2008 Sem

inar Feedback;2009 ahead

Torque Converter Rebuilders AssociationPO Box 2546Reno, Nevada 89505

Do you

hav

e a

prod

uct

you

’d li

ke to

market? Do you have items for sale? If so, advertise in the newsletter!!

Become a sponsor of the

Torque Converter Rebuilders Association. By becoming a gold or

platinum sponsor, you’ll earn extra cov-erage on our web site, and attract the busi-

ness you are looking for. Platinum Sponsors appear on all printed material, including mail-ings, handouts and magazine advertisements. Each sponsor also receives web space ex-posure to thousands of tcraonline.com

guests. Members can earn a 10% dues reduction by setting up automatic

credit card payments.

Items For Sale

Contact Information

TCRA thanks all gold and platinum sponsors!

Gold Sponsors:

Got items for sale?

As a member of the TCRA, you can advertise for free right here, right now! Also have your

items posted online.

Email [email protected]

Mark Mustard [email protected]

Ed Lee ..................... Vice [email protected]

Dick Lewis [email protected]

Chris Mann [email protected]

Ken [email protected]

Steve [email protected]

Ken [email protected]

Don [email protected]

Joe [email protected]

Dennis [email protected]

Jan [email protected]

Jeff [email protected]

Len [email protected]

(973) 293-8925

Questions or comments? Contact the TCRA newsletter by e-mail at [email protected] visit the web www.tcraonline.com or contact Dennis Sneath, board member and newsletter committee team lead.

I am sure that any of us in the converter busi-ness have heard that statement; in this case

the converter was a ZF 5HP19 of the captive clutch type fitted to an Audi AWD. We had overhauled the converter in question about a month before and now my customer, who was a transmission rebuilder in another town about 350 miles away claimed that the con-verter shuddered during the regulation phase. As always my first question was what fluid have you used in this? Answer was “Dexron 3” so I suggested that he might like to change to either the correct specification fluid or an equivalent. This he did and reported that the shudder was now gone. About three weeks later he called again with the statement that the converter was once again shuddering. At this stage I decided that there was no real answer apart from to get the unit back and check it. This was done and the converter split. There was no evidence of any problem so I advised him of this and suggest-ed that he check the transmission carefully. The converter was assembled with new lining and extra care on the clearances. It was fitted and the report was that the shudder was once again gone. This time it was about a month and he re-ported that his customer was once again com-plaining of a shudder, he had tried another valve body and was now squarely blaming the converter. He suggested that perhaps he should send the converter to another rebuild-er because it appeared that we were not hav-ing any luck and the competitor assured him that he would be able to do the job with suc-cess. I was reluctant to allow this to happen, as he is a good customer so after asking vari-ous people and hearing that often the fault could only be cured with a factory converter I offered to obtain a factory unit for him. The factory unit arrived and was fitted; ve-hicle drove well with no shudder. This time once again for about a month and the cus-tomer is back once again with the same com-plaint. At this stage I said that I was out of ideas and the only way that I could help him

was to have the vehicle. I should mention here that we are also a transmission shop. Vehicle arrived and sure enough it had one of the worst shudders that I have ever felt in a converter. We checked the obvious exter-nal things such as engine codes etc and then removed the pan. This is where it gets inter-esting. The technician that removed the pan reported that the fluid had a strange look to it. Not pink or discolored but “Just doesn’t look right” At this stage I remembered that at the last TCRA seminar there was a brief mention of testing for water using a coffee maker of the filter type. A drop of the fluid on the hot plate and it sizzled. A sure sign of water. A re-port to a disbelieving customer that the fluid was contaminated with water meant we had to have a professional test carried out and this came back with 2% water contamination. Converter rebuilt with new lining transmis-sion rebuilt with new clutches, refitted to vehicle along with a new radiator and all is well. It turned out that the radiator was leak-ing coolant into the fluid, not a lot but just enough to change the frictional characteristic of the fluid. Of course each time the fluid was changed the problem was gone until the con-tamination reached the critical level again. So what is the moral of the story? Think out-side the square don’t take anything for grant-ed and remember the quick and easy test for water. Just put a drop on the hotplate of the coffee maker, if it sizzles and spits there is likely to be water contamination and if it just smokes the fluid is ok. Remember the fluid can look good and still be contaminated.Of course the best part of this whole story is that I retained my customer and was paid for all the converters and the transmission job as well as a radiator!

Martin BrooksAceomatic Transmission Services

Christchurch, New Zealand

Tech Tip: Water contamination a possibility

Check out next month’s editionof the TCRA newsletter for

pictures and coveragefrom this year’s seminar.

Can’t wait until next year? Join us in June 2009 in

Cookeville, Tennessee andtour Dacco, 2009 seminar host!

Documents

DC-1000/2000 Improvements