Thread: slight shudder from auto trans

Yep.............Google is your friend.
Regards,
Tote

Now I have had recently auto issues, with slight shuddering in top gear under load..
I have taken the car to the dealership, and had the full auto service completed. It was expensive and did not solve the problem, but the up side the gear changes are certainly smoother.
After considering my options and ringing around for second hand auto trans, to recon ones to new autos, the cost was at worst $9,000, yes $9.000 quoted for a new auto installed by the dealership, and the cheapest $7,000.
After further research l found out from my local Auto Trans business, that he has fixed quite a few D3's, and the issue is the Torque Convertor. Cost to repair $2200.
Easy to identify symptoms are particles in the trans fluid after the main service, attributing to the degeneration of the material in the TC>
Not main trans issues, as the gear changes are smooth at all times, inside the shudder range in top gear under load.
I can live with this cost, if the outcome is a fully operational auto trans.

Lets hope this will be fixed once and for all

I Got the oil test results back from my trans oil this week. I am wondering if I have a porous transmission cooler. After questioning my results I got the following reply from oilcheck.

"We don’t actually have a method of directly measuring for Glycol yet, but sodium, potassium and water are indicators of coolant contamination. We used to report a glycol result by FTIR, but the accuracy of that value was found to be poor. We are still looking into a Gas Chromatography headspace method for the accurate determination of glycol, and we are likely to be able to offer this in the future.

Your sample though has elevated sodium content which almost always suggests coolant leakage. Water can evaporate from the oil leaving sodium, but I did question the very low water result. I’ve had the sample retested manually with the small amount of sample left, and actually found there to be an elevated water result of 0.13%. This along with the elevated sodium is further evidence of coolant contamination. Salt water is also a possibility if the vehicle has been in such an environment."

Unfortunately it's a bit hard to gain any meaningful info without a baseline as the oil has done 145000KM including some water crossings and week on Fraser Island. I'll certailnly be doing another oil test after the transmission problem is sorted.
I am very happy to recommend oilcheck who provide very good response and customer service. Oil testing laboratory, oil analysis laboratory, oil condition monitoring, oil testing services Sydney Australia - OilCheck Pty Ltd You can order a sample kit over the web and pay using paypal. The test kit arrives with instructions and return mailing paid. Overall a very good service.

Regards,
Tote

Based on your suggestion, when I recently had the local ZF transmission shop do the oil and pan/filter change on my ZF6HP26, I asked them about doing an oil analysis.

They looked at me sort of sideways, but did say that when they drain the oil, they can tell so .... As it turned out, the oil looked OK however it did not take sampling to see the metal bits stuck to the magnets - fortunately nothing much to yet get excited about at this time.

It is a totally different story with my airplane. Whenever the maintenance people change engine oil, (Lycoming O-320 E2C), they take a sample and send it off. We then compare it with the previous test results. This works well with aircraft engines as one is looking for metal contamination - or more correctly, how much more metal than last time and what is the stuff so we can sort of figure out what is wearing from the type of metal the results pick up.

Folks, l will have the Torque converter repaired on my D3 next tuesday.
I hope to shed some light on some shudder symptoms, and hopefully it will help us all understand the issues, and may save money on an expensive repair.

Interesting development on the auto trans shudder.
It seems that quite a few people who have auto trans issues, such as a shudder, seem to think the auto is worn out.
Various advise from dealerships and local workshops indicate a replacement of the auto trans box.
I contacted a reputable auto trans workshop on the Gold Coast, who has worked on D3's.
After some detective work, we discovered that the Torque Convertor is the issue.
The TC was showing burn marks etc from slipping.
Degeneration of the TC contaminates the auto trans fluid, and blocks the fliter.
The TC is the direct result of the shudder, and not the auto trans itself directly.
I hate to imagine how many people have been slugged huge amounts of money to replace an auto trans box.
The cost to repair my car is under a third of the cost, and solves the issue.
I thought l would at least share my expereince, and maybe if someone is experiencing the same issue, explore the option of the TC.
(1 Torque Convertor degeneration and shudder creating burn marks
(2 Degeneration of material fouling the auto trans filter

I am no mechanic, but understand the issues car has had, and the solution that saved me alot of money !!!

Where did you take it Busman?

Originally Posted by unseenone

Where did you take it Busman?

Russells Automatics
Siganto Drive,
Oxenford,
Queensland,