Miracles Do Happen - Transmission Digest

Miracles Do Happen

A 1995 Jeep Grand Cherokee was brought to a Cottman Transmission shop in Jennings, Mo. The customer‘s complaints were typical for this model transmission and correct for the mileage of the vehicle. A complete transmission and converter rebuild were sold and, because of the chronic cooler-line problems, a cooler-line update was sold for added security.

Miracles Do Happen

TASC Force Tips

Author: Ed Lee, Deltrans

Repair Kit Saves Cracked Case on A500 (42RE/42RH) & A518 (46RE/46RH)

TASC Force Tips

  • Author: Ed Lee, Deltrans

Repair Kit Saves Cracked Case on A500 (42RE/42RH) & A518 (46RE/46RH)

There are times when even the most-routine task can turn ugly in the blink of an eye. When this happens we could all use a little help, sometimes even a small miracle.

A 1995 Jeep Grand Cherokee was brought to a Cottman Transmission shop in Jennings, Mo. The customer‘s complaints were typical for this model transmission and correct for the mileage of the vehicle. A complete transmission and converter rebuild were sold and, because of the chronic cooler-line problems, a cooler-line update was sold for added security.

Technician Andy Hanneken performed the rebuilding chore, then handed the unit off to the R&R man.

The R&R went flawlessly right up until the new cooler-line fittings were being installed. When the rear cooler-line fitting was installed into the case, there was a loud cracking sound as the case split (task turning ugly). The sound of a case breaking gives you that sick feeling in your stomach, like the one you get when the love of your life says goodbye for the last time. In fact, about the only cracking sound that is worse is the one you hear on a ski slope when it is one of your own bones breaking.

It would have been easy at this point to look back and talk about what could have been done to prevent the case from breaking. Yes, removing the factory-installed sealant from the threads (see Figure 1) with a wire wheel and installing a good liquid thread locker might have been a big help. Simply applying less tightening torque might have prevented the break, but this 20/20 hindsight was too late.

Andy contacted Cottman’s international troubleshooter, Brian Workman, and told him about the problem. (Enter small miracle.) Brian told Andy that he had heard of a prototype cooler fitting to repair cracked cases that could be installed without removing the transmission from the vehicle. This was especially good news for Andy, because not only would the costs of an additional R&R and case swap be bad enough but also replacement cases sell for a premium in his locale.

No kits for the repair fitting were available at the time: However, Brian was able to get a prototype fitting and Andy was able to piece together the other components.

Besides the fitting, one of the other key items in the kit is a tap. We were all taught that pipe threads are tapered. This fact allows them to be tightened to prevent leaks. Of course, this is also what splits the cases. The NPT (National Pipe Thread) tap cuts a tapered thread. Also available is an NPS tap that cuts a straight thread. The NPSF tap cuts a straight thread that is fuel grade. A machinist would call this a Class 3 fit.

Andy had the NPSF tap along with a bottle of 609 Loctite™ (the other key item) sent to the shop by overnight delivery, and Brian sent the repair fitting.

The original cavity was threaded well past the cracked area with the new tap (there is plenty of room to do this). The fitting was coated with 609 Loctite and screwed into the case well past the cracked area. The original fitting, which cracked the case, then was screwed into the repair fitting and the replacement lines were installed (see Figure 2). The new setup was leak free, and life was back to normal for Andy.

Don’t you love a happy ending?

The TASC Force (Technical Automotive Specialties Committee) is a group of recognized industry technical specialists, transmission rebuilders and Sonnax Industries Inc. technicians.

You May Also Like

GM 6T40 Pump Identification Guide

The 6T40 was introduced in 2008 for General Motors front-wheel-drive cars in the Chevrolet Malibu and has gone through several changes throughout its three generations, specifically in the pump area. The 6T40 is closely related to the more lightweight 6T30 and the heavier duty 6T45 and 6T50. Generation one started phasing out during the 2012

The 6T40 was introduced in 2008 for General Motors front-wheel-drive cars in the Chevrolet Malibu and has gone through several changes throughout its three generations, specifically in the pump area. The 6T40 is closely related to the more lightweight 6T30 and the heavier duty 6T45 and 6T50. Generation one started phasing out during the 2012 model year. The generation two pump had a slightly different pressure regulator valve, but overall the first two 6T40 generations had the same pump layout.

Seeing the Forest AND the Trees

They say that the proverbial phrase “I couldn’t see the forest for the trees” means that a person or organization cannot see the big picture because it focuses too much on the details. Related Articles – The Manifold Pipeway – 8L90 Vacuum Testing – 4L60E Harsh 1-2 Shift I have seen this phrase used after

The Manifold Pipeway

The Honda six-speed transmission has been on the bench of many specialty shops for one reason or another (figure 1). But, for those of you who have yet to lay your hands on one, mounted on the upper side of the unit is one of the largest, if not the largest solenoid and pressure switch

8L90 Vacuum Testing

Below are the diagrams for vacuum testing GM 8L90 transmissions. Note: OE valves are shown in rest position and should be tested in rest position unless otherwise indicated. Test locations are pointed to with an arrow. Springs are not shown for visual clarity. A low vacuum reading indicates wear. For specific vacuum test information, refer

4L60E Harsh 1-2 Shift

The 4L60E transmission platform has been in service from 1993-2015; that’s 22 years. It amazes me when a transmission that has been around for this long can throw a new twist on a common problem and blindside you. Let us have a look at the systems and potential problems in a 4L60E that can cause

Other Posts

How to fix GM 8L45/8L90 no-move and no-pressure conditions

By now you may have heard of, or even experienced, a GM 8L45 or 8L90 transmission with a no-move or no-pressure condition. Conditions of no movement or no pressure after repair have plagued this unit since its inception. Here’s what you can do about them. Related Articles – Ford harsh downshifts: 6R75 2-1, 10R60 7-6

Tasc-Force-December-Figure-1-Pressure-Regulator-Valve-Assembly-Correct-1400
TransTec introduces Power Steering Gear Seal Kit for Jeep Wrangler

TransTec has introduced a new Power Steering Gear Seal Kit for Jeep Wrangler. Related Articles – Alto releases filter for Nissan GR-6 dual clutch transmissions – Alto introduces steel plate for GM transmissions – GFX introduces new oil pan lines for various GM transmissions According to TransTec, the gear seal kit includes everything needed for

TransTec-Power-Steering-1400
Stop/start accumulators: What you don’t know can hurt you

It’s no secret that the auto industry is making big moves these days, but while a lot is new, one thing that never changes is that the men and women servicing vehicles need to be learning almost constantly in order to do their jobs safely and effectively. Everybody knows not to touch hot exhaust parts,

Figure-1---Stop-Start-Accumulators-1400
How to get started with OE ECU reprogramming

The conversation goes like this: I have been paying mobile programmers or remote access programmers (RAPs) far too long. I believe I can save money and time by doing this myself. What type of equipment is needed and what is the cost to get up and running? Related Articles – Shift Pointers: Reassembling GM pumps