do you have a "telma-retarder"?

After someone was kind enough to forward an original build sheet for my van, I looked over the codes and found two which intrique me: WM9 Telma--retarder CC80 and WW6 Telma-retarder CC80.

I found limited information on the web, but seemed to eek out that it has something to do w/ electromagnetism and braking located around the driveshaft (or elsewhere?). My van was a fleet vehicle, so maybe more prone to be ordered with devices such as this.

a) where is it located?
b) do I really have 'two' of them?
c) does everyone have at least one Telma-retarder?

A) followup: IFF not every van has a CC80 braking device, is the lacking van more prone to worn rotors?
B) followup: IFF not every van has a CC80 braking device, has anyone driven a van with and without to determine the different 'feel'?

within the last month I was responding to a post on this forum and the topic of braking came up where as my description is that the van feels as if it is braking itself (above and beyond the hydraulic brake system). Someone commented that this may be due to the cylinders shutting down due to lack of fuel (defueling).

A Telma Retarder assists with repeated heavy braking. It's an unusual option - you'd typically see it being specified on an ambulance for example, fitted to the prop. You haven't got two: one option code is pre-install prep for it, the other is the retarder itself.

Mine doesn't have a retarder and I can get 200,000kms out of a set of discs, so no I don't feel it's more prone to wear. Not driven one though.

The Telma retarders are often on heavy trucks that work in mountain territory, or steep grades. Common on off highway vehicles, I have used them for construction equipment like Transit Mix trucks that have to deliver down in a deep canyon.
They are metal rotors installed on the drive shaft and a set of electromagnetic coils that induce a field in the rotor, aluminum I think, and creates eddy currents circulating in the rotor...no contact. The resulting heat that reflects the 'braking' is rejected through openings in the spinning rotor vents.
Very reliable, nil wear. Can be fouled by mud, impacted by water. Simple mechanism though the drive shaft is a slow speed place to put a retarder. (others work at higher speeds such as internal to the transmission as on the Allison hydraulic retarder).
It functions like a jake brake in the point that it is a brake without issues of pads and friction, heat and fading. Most are adjustable in having a variable number of electormagnets energized - to select the effect. The resisting torque varies with a squared relationship to shaft speed, so usefulness at low speed is limited.
You should be able and find specs on the internet.

I live in the western usa, and if hauling a heavy load through on I5, I would like one. I would estimate the cost to be $2000 but less as a component, more as a mercedes item. Needs a bit of engineering to install, and electical power/control is simple but not minor.

Dale dronsin

In another thread involving a Winnebago View, https://sprinter-source.com/forums/showthread.php?t=9226 the Thelma-retarder was listed on his build sheet.
WP5 TELMA-RETARDER CC80

--dick

thanks-I located island's build sheet ealier and had noticed he had the WP5 code.

even though my van has two codes relating to the telma-retarder, I don't see anything like that on the driveshaft. does anyone have a master list of what the codes relate to?

We are waiting for such a list.

Chrysler called the book describing the Chrysler sales codes a "special equipment book." It was stored on the NAFTA Bodybuilder website for NAFTA Sprinters.

All the Chrysler "special equipments books" have been deleted.

MB has not provided NAFTA with a whole list of MB sales codes and equipment descriptions, yet.

They may not.

-Jon

Extracted from:
Mercedes-Benz body/equipment mounting directive for the Sprinter, Edition: 17.06.2004

6.6.6 Auxiliary brakes/retarders
If a retarder is retrofitted to the transmission or the propeller
shaft train, a certificate of endorsement is required
from the department responsible (
page 14).
Certificates of endorsement are not issued in all cases.
They are limited to specific vehicle model series and
wheelbases.
The installation drawings must contain the following information:
 Location of retarder in the vehicle
 Propeller shaft angle
 Length of propeller shaft
 Due to the additional weight of the retarder, the load
distribution must be verified as well as compliance
with the permissible axle loads. The location of the
body's centre of gravity and the distance between
the rear axle and the semitrailer coupling point must
be verified and adjusted, if necessary.
 Installation is only permitted if the vehicle electrical
system has sufficient capacity.
 (Alternators and batteries must have sufficient capacity.)
Make sure that the retarder earth connection
has sufficient rating.
 Make sure that there is adequate freedom of movement.
 Only secure retarders in the propeller shaft train to
the chassis frame web by means of brackets fitted
with silent blocks.
 Lines must be protected from heat by means of insulation.
The maximum permissible temperature for
compressed-air lines made of polyamide is 80 °C.
Installing propeller shafts
!
If you intend to retrofit a retarder, you can obtain instructions
for retarder control on Sprinters equipped
with ABS/ASR or ESP from the department responsible

Cheers

Ross

Brilliant Ross I have seen these and been in Sprinters in Europe and the Middle East with them fitted but only on manual! I was never sure if they could be retrofitted to an automatic.
Great write up
Richard

"Retarder" is also mentioned in the 906 body builder book (more apropos to the NCV3).

https://sprinter-source.com/forums/showpost.php?p=8871&postcount=1

-Jon

Not exactly current, and doesn't mention the retarder, but it has a lot of other info...
View attachment Sprinter Body Builder Info Book.pdf

My vehicle datacard indicates four build codes for the thelma Retarder; WM9 TELMA-RETARDER CC80, WP5 TELMA-RETARDER CC80, WV0 TELMA-RETARDER CC80, and WW6 TELMA-RETARDER CC80. And for what is is worth--I do not see anything like discribed above on the drive shaft sections or supports.

NCV a telma retarder is UK option 229 UK pounds fitment of preparation for option telma retarder extra cost is a 1995 UK pounds as Mean in Green has stated above to maximize deep decent on braking to minimize brake wear.
Richard

aeroshots said:

My vehicle datacard indicates four build codes for the thelma Retarder; WM9 TELMA-RETARDER CC80, WP5 TELMA-RETARDER CC80, WV0 TELMA-RETARDER CC80, and WW6 TELMA-RETARDER CC80. And for what is is worth--I do not see anything like discribed above on the drive shaft sections or supports.

Click to expand...

This is very confusing! I have 3 build codes for the telma retarder an my data card: WM5 TELMA-RETARDER CC80, WVO TELMA-RETARDER CC80, WM9 TELMA-RETARDER CC80. I haven't gone underneath the van since the day of delivery when I had the dealer put it on the lift for me. One of the things I wanted to check out was thee drive line and I sure didn't notice anything like what's been described. To confuse even further, I had a local Chrysler/Dodge dealer run a vehicle report for me and there is absolutely no mention of a Telma Retarder or anything similar on the Options part of that report. There are several items on this report that are a total mystery to me; for example 2TBA Customer Preferred Package 2TB and 22B Customer Preferred Package 22B. Does anyone know what is included in these packages?
It sure seems that there ought to be a way to demystify these goofy codes!
Wayne

I have 3 apparently. They are also called electric retarders.


This one is in the brake system somewhere.

Regards,

Keith

72chevy4x4 said:

I was responding to a post on this forum and the topic of braking came up where as my description is that the van feels as if it is braking itself (above and beyond the hydraulic brake system). Someone commented that this may be due to the cylinders shutting down due to lack of fuel (defueling).

Click to expand...

this post by me six months ago...after seeing this post pop up I 'noticed' that the feeling of the van braking itself is no longer present. I wonder why?

Keith,

Did you get your exploded parts off of EPC online? If yes, can you tell me the vehicle model (ex. 906-655) Major group (ex. 42 Brakes) and subgroup (ex. 030 Front Wheel Brake) you were using? I have been all over EPC looking for this and can't find it. Of course I don't really know what the heck I'm doing in EPC.

I was in Sprintertek. I paid for a 24 hour subscription. I was doing a search based on my VIN. I have three retarders but the one on brakes is all I could find. I have not checked it out in EPCnet but it probably won't be there.

I wish Sprintertek was cheaper.

Regards,

Keith

kmessinger said:

.

I wish Sprintertek was cheaper.

Regards,

Keith

Click to expand...

I wish it were cheaper as well. Unfortunately, we're not entitled to free information from MB's service library (or cheap maintenance, either).

On the bright side, after the revamping of techauthority.com, the Chrysler Sprinter information is still less accurate and techauthority subscriptions are now more expensive than www.Sprintertekinfo.com.

Learning has a currency tuition, mental stress tuition and - if you're gonna do it yourself - a physical/sore muscle tuition.

Regardless, I am really glad you ponied up the dollars and got a gander at www.SprinterTekinfo.com, Keith.

-Jon

Altered Sprinter said:

NCV a telma retarder is UK option 229 UK pounds fitment of preparation for option telma retarder extra cost is a 1995 UK pounds as Mean in Green has stated above to maximize deep decent on braking to minimize brake wear.
Richard

Click to expand...

kmessinger said:

I have 3 apparently. They are also called electric retarders.
View attachment 24646

This one is in the brake system somewhere.

Regards,

Keith

Click to expand...

Telma electric magnetic retarder of which is fitted with ABS interface,including ice/snow functioning.sort of like a jakes brake.

wayneskid said:

There are several items on this report that are a total mystery to me; for example 2TBA Customer Preferred Package 2TB and 22B Customer Preferred Package 22B. Does anyone know what is included in these packages?

Click to expand...

From the 2007 and 2008 Dodge brochures: 2TB includes luxury driver and front passenger seats, hinged lid for center stack, driver seat base power outlet, locking glove box. Passenger van also includes light group, left and right rear seat armrests, rear door wiper/washers, rear seat cupholders.