July 2010 Archives - Transmission Digest
Valve-Body Reaming

When it comes to reaming valve bodies, there are always questions about how to approach things the “right” way. It pays to keep in mind that reaming a valve-body bore to allow installation of an oversized valve or sleeve is a precision operation and must be viewed with the mindset of a machinist. Properly maintained equipment, correct setup and the right cutting fluids are critical in achieving success. Here are a few suggestions we have compiled over the years in response to common inquiries.

The Hotrod Jeep New Venture Gear 146 Transfer Case

SRT8 stands for “Street and Racing Technology,” which is the performance group of Chrysler Corp, and the 8 signifies a V-8 engine. The SRT people put a whole lot of oomph into this vehicle, designed to compete with the BMW X5 and X6 models and comparable Mercedes-Benz SUVs. Powered by a 6.1-liter Hemi engine, the Grand Cherokee SRT8 is the second-fastest vehicle in the Chrysler line, surpassed by only the Dodge Viper with its V-10 power plant.

July 2010 Issue

In This Issue
Ford/Mazda 4F27E/FN4A-EL: Delayed engagement/low pressure
Ford 4F27E: 2-3 upshift concerns
Dodge/Jeep 42RLE: Low power in reverse
Chrysler/Dodge/Jeep RE-Series Transmission

Issue Summary:

After overhaul, Ford and Mazda vehicles equipped with the 4F27E/FN4A-EL transaxle may exhibit a delayed engagement or a low-pressure condition.

Before or after overhaul, a Ford vehicle equipped with the 4F27E transaxle may exhibit a complaint of a sliding or flared 2-3 upshift.

A 2005-2006 Dodge truck or Jeep with a 42RLE has a lack of power when backing up an incline while loaded or pulling a trailer.

A new governor-solenoid conversion kit is available for the RE-series transmission to improve reliability and performance.

45/545RFE Pump Mystery Solved

This article refers specifically to Dodge trucks equipped with 45/545RFE transmissions. Because Dan’s shop works on many of these units, which are known to have pump issues, he stocks new pumps on the shelf. When Dan called he explained to me that when he disassembled one of these brand-new pumps he noticed that the screws that hold the pump spacer plate to the pump body were missing. He wanted to know whether this could be some kind of assembly-line error and whether he should exchange the pumps for new ones.

‘New’ Does Not Equal ‘Good’

Diagnosis is a challenge for any shop. Sometimes things can get even more complicated because of a previous repair, or a part that has been replaced recently. This case involves both of these scenarios. After all, we really want to believe that a new part is a good one, right?

No Rear Lubrication

A JR403-E transmission from a 1995 Isuzu NPR came in over the counter to Luis Zabala’s transmission shop in Miami for repair of a front-seal leak. The unit was examined for damage because of the possibility of low-fluid-level conditions. The only wear or damage discovered was the pump bushing and seal.

Like Little Children

If you didn’t choose your words very carefully when you asked the kids to do something, they would pout and sometimes disappear for a day or two. Most of them drank, so the disappearing act wasn’t a big surprise. These guys were protected by what was at the time a very strong union so they felt as if they were invincible. Today they would be lucky to keep their jobs at all, what with the line of unemployed workers looking to replace them.

Grand Am No-Start Presents Challenge

I haven’t thought about that dream for a long time. Then I found myself working on this ’93 Pontiac Grand Am no-start. It’s a 3.3-liter V-6. It has the characteristic look of a car that has been saved for slow times, judging from the rusty belt (Figure 1).