Transfer case Archives - Transmission Digest
Infiniti G37 RE7R01A chassis codes set

The complaint A 2013 Infiniti G37 equipped with the RE7R01A transmission and the EXT13C transfer case has a complaint of trouble codes C1204 “4WD Solenoid Malfunction” and C1105 “Right Rear Wheel Speed Sensor Fault” stored. Due to extensive damage, the transfer case was replaced, which did not eliminate the stored codes. The shop then replaced

S-Tec Complete Transfer Case Assembly for GM Trucks

The NP263 transfer case is chain-driven with an electric shift.

Snow plowing = BW 44-44 transfer-case failures

Experience we gain from solving problems generated in the transmission repair industry sheds light on various common failures and allows us to see trends that provide new products to solve design issues.

From 2011 on, Dodge has offered Ram 1500 pickup trucks equipped with the BW 44-44 transfer case. The 44-44 transfer case is a computer controlled “active” full-time transfer case.

BorgWarner 44-44 Transfer Case from the Electronic Side

Last month we took a look at the BW 44-44 and 44-45 series of transfer cases found in late-model Ram pickups. We continue this month with a look at the electronics that make the 44-44 function. A brief review on this unit leads us to an electronically controlled active full-time transfer case.

Transfer Cases and Tires: How RAM is changing the rules

Looking at the BorgWarner 44-44 and 44-45 transfer cases, we see an evolutionary change that started with the BW4405 and 4411 and has now reached this level of development. The design uses a wet-clutch pack in the transfer case to split torque between the rear and front axles.

Getting into the MP3023 Transfer Case

Getting into the MP3023 Transfer Case

Magna Powertrain (MP) is a worldwide manufacturer of components and systems for vehicle manufacturers. It has acquired the New Process and New Venture Gear business and now produces components under the Magna name. GM awarded its transfer-case business to Magna beginning with the 2007 model year. We have done articles before on the various models of MP transfer cases.

PTU: a Different Kind of Transfer Case

The main design parameters for most late-model cars have been front-wheel drive (FWD) with transverse-mounted engines. This is a convenient packaging system for the manufacturer and has been for many years. The current trend of increased safety and performance has made many of the manufacturers add all-wheel drive (AWD), which sends power to the rear wheels for better traction and stability. The traditional transfer case, which divides power to the front and rear axles on vehicles with north/south engine placements, is unusable here.

Metallurgy + the Laws of Physics = Buyer Beware

The car sat on the lot for about a month, until a salesman noticed a collection of white/gray powder under the middle of the vehicle. Curious as to what was going on the salesman went to move the Hummer, put it in gear and promptly blew the rear driveshaft out of the vehicle. They then removed the BW 4484 transfer case from the vehicle. By looking at the photos provided here, you can see what happens when a transfer case with a magnesium case is filled with seawater for more than a month. The case is now paper thin and riddled with holes as if attacked by metal-eating moths. The used-car lot bought a new BW 4484 and fixed the problem. The core was sent to us, and it makes a good basis for this article.

Magna Powertrain Transfer Case, RPO Code NQF

We finally had a big-enough snow this year to bring out the people with 4WD problems. This one was a 2008 Chevy Silverado 2500 HD.

It was from a tire distributor that has a number of these particular trucks. Their technicians had been trying to fix the issue of having no 4WD by putting various parts on it. They said that they had replaced the transfer-case motor and buttons.

I started out with the usual road test, scan and lift check to verify the problem. Sure enough, there was no 4WD and the transfer-case control module (TCCM) had every code possible stored. I thought I’d clear the codes and start out fresh.

Magna Powertrain Transfer Cases, Part 2

In last month’s article we identified and explored the basics of the Magna Powertrain transfer cases found in late-model GM trucks. In this article we take an in-depth look at one of the three series of models available: the MP 1222, 1225 and 1226 models, using RPO (regular production option) code NQG.

Understanding the significance of the RPO codes on GM vehicles will make parts ordering simpler. Figure 1 shows the variations and descriptions of the NQG series of transfer cases. As these units are used in K1, K2 and K3 models of trucks, there are differences in input and output splines, chain size and number of pinions on the planets. These variations provide the torque capacity necessary to cover the different engine/transmission combinations for light-duty, heavy-duty and super-heavy-duty applications.

Humming Along with the BorgWarner 4493/4494 Transfer Case

GM had great sales for a time with the Hummer brand. The economy has foreclosed on that segment of the market, and GM has sold the brand to a Chinese company. However, there are lots of Hummer H3s around and no dealer body to repair them, which sounds like opportunity for the transmission shop.

The Hummer H3 was available with either an automatic or manual transmission and used a 4493/4494 transfer case manufactured by BorgWarner. The 4493 and 4494 are operationally the same transfer case, a three-position, electrically shifted unit. The 4493 has a 2.64 low-gear ratio and the 4494 has a 4.1 low-gear ratio, which makes it a good rock crawler for the off-road guys. This obviously means that the internal gear trains will be different.

Revisiting the New Venture 246 Transfer Case

The New Venture 246 transfer case has been in production since 1998. New Venture, however, is no longer with us, having been acquired by Magna International, a large conglomerate that is a tier 1 supplier to many of the global auto manufacturers. I wrote a previous in-depth article about the NV246, which you can download from our website ( for free, explaining the workings of this active-transfer-case theory of operation and electronic controls. Go to Technical, and find NV 246, Understanding the Tricks, under the transfer-case section. This article describes the design changes and the fixes for common problems and design defects for this unit.