Replacing front leaf spring

Zundfolge

Always learning...
There doesn't seem to be a solid writeup on this one so here we go...

My thread asking about when to replace the front spring:

https://sprinter-source.com/forum/showthread.php?t=77566

A writeup that has pictures from the service manual:

https://sprinter-source.com/forum/showthread.php?t=19476

Finally a writeup that helped some, but I honestly had trouble reading it and found it more useful to read the service manual instead:

http://www.mercedes.gen.in/mercedes-sprinter-front-spring-replacement/

My front spring seemed tired, wasn't hard to bottom out the front. I asked on my thread how to tell if it was getting tired and the general response was that if the bump stop was less than an inch from the stop plate on the lower control arm (LCA) it may be starting to get tired. Mine was around 1/2"-5/8", I couldn't get a finger in between, so I opted for replacement.

The spring was $200 from europarts, seemed to be the best bet and OEM quality part (I'm not affiliated with europarts, but they do source generally good parts for a decent price). You also need 2 new top bushings, and a left and right bushing, so 4 total. I'll try to edit in p/n's for those.

This job would go well with two people, but I'm only one and I still got it done, though not without a certain amount of beer and profanity.

____ _____ ____ _____ _____ ____ _____ ____ _____ _____

1) WITH VAN ON THE GROUND remove the front and rear bolts from BOTH left and right spring clamp plates - you cannot get to the nuts once van is in the air!

IMG_2677 by Nicholas Tavasieff, on Flickr

2) Jack van up and support with jackstands, and I typically will then stack blocks of wood or something similar like use a screw jack to make extra sure I'm safe under there. Remove both front wheels.

Note: I removed the spring from the drivers side (USA/NAFTA/NAS drivers side) and so will say when something is to be done on one or both sides.

3) Remove drivers side brake caliper adapter - not from the slide pins. 2 bolts, 18mm IIRC? Support the caliper out of the way properly and careful not to sharply bend any brake lines. it sits nicely on the little ledge behind the strut.

IMG_2684 by Nicholas Tavasieff, on Flickr

4) Remove ABS sensor - I used a cat's paw using many light taps and it came out easily.

IMG_2685 by Nicholas Tavasieff, on Flickr

5) Separate outer tie rod end from steering knuckle. I loosened the retaining nut until the top of it cleared the tie rod's threads, then banged down on the nut (NOT the tie rod end threads!) until the tie rod broke loose. Then remove the nut and pull the tie rod all the way down and out.

IMG_2687 by Nicholas Tavasieff, on Flickr

6) Remove the strut. Pull back the floor mat on drivers side, I used an impact wrench with a 24mm socket to blast the nut off of the top of the strut. Then remove the 4 bolts attaching the strut to the steering knuckle.

7) Remove bolts - 3 each - from drivers and pass side stop plates. Leave the sway bar and links attached, just swing the plates out of the way.

NOTE: The manual says to remove the ball joint nuts and separate from steering knuckle but I didn't find that necessary.

8) Remove the bolts from each side of the drivers side LCA, and pull the LCA and steering knuckle assembly out of the way. IIRC the bolt is 19MM and the nut is 21MM or 7/8"? You can't reach it with a socket so you'll need the proper size wrench.

9) Support the now open end of the transverse leaf spring with a jack and put some upwards pressure on it. Next step is to remove both spring clamp plates, dr. and pass. sides.

4 - 16MM nuts and bolts on either plate.

10) Release jack and pressure will now be off of spring. BE CAREFUL and stay out of the way any time you have pressure on the spring. If something goes wrong you do not want to be in the path of that thing with tension on it! Now you can roll and remove the spring.

IMG_2693 by Nicholas Tavasieff, on Flickr

INSTALLATION

11) Push the new spring into the pass side LCA as snugly as you can. Make sure the rubber end is fully seated against the end of the spring. Set the new top bushings into place, a little grease may help them seat into position when you start applying pressure. They must be installed in a way that they seat into the upper color coded mounts.

NOTE: I had trouble with getting the spring seated in the center and ended up having to go back a bunch of steps because of it, and it was already like 10 at night so this is where the bulk of the swearing occurred.

12) Making sure the new spring's rubber end is snug against the LCA cup (on pass side), and top bushings are in place, begin jacking the drivers side end of the spring up, making sure you pad the jack with a piece of wood so you don't damage the new rubber end. Reinstall the drivers side spring clamp plate, making sure you use the correct new bushing on the drivers side! Working from bolt to bolt, never fully cranking one down. There are two guides on the front and back-most bolt holes that must line up (the holes that you can only access the nuts to while van is on ground). Swear a bunch. Get it good enough, it may not be all the way tight yet, that's ok.

13) With drivers side spring clamp plate at least mostly tightened down, you can reinstall the LCA. Release jack, setting spring tension down onto the spring clamp plate. Here is where I switched to a screw jack underneath the LCA to help push things into place, and be able to line up the LCA into its holes. I also dabbed some grease onto the LCA bushings to help them slide around a little better. Once installed don't tighten all the way, you can do a final LCA tightening with van on ground.

IMG_2699 by Nicholas Tavasieff, on Flickr


14) Reinstall the Pass. side spring clamp plate, again making sure you have the correct bushing on top of the plate, working from bolt to bolt and lining up the guides.

15) Reinstall the stop plates, dr. and pass. sides.

16) Reinstall dr. side tie rod end.

17) Reinstall strut.

18) Reinstall ABS sensor. Push it back into the hole until it gently makes contact with the tone ring. As soon as it touches its good, they self adjust for the correct gap when you drive.

19) Reinstall brake caliper.

20) Reinstall wheels, and lower van to the ground. Now you can reinstall the front and rear bolts and nuts onto the spring clamp plates, both pass. and dr. sides. Then make sure the 4 16MM bolts and nuts are torqued to spec.

21) Give a final torque to spec for the LCA bolts. 150N-m (110 ft. lbs.)

That's it.

You may want to get your alignment checked after this job, good luck!
 

glasseye

Well-known member
Superbly documented. :thumbup: Both words and pictures.

As a photographer, I'm frequently amazed at how well people shoot, especially under auto repair conditions.

Again, nice work, Zundfolge. :rad: Thank you from the future, when one day I might have to tackle that job.
 

Theory&Practice

New member
My front leaf spring is dead, and I'm looking at replacing it. There's a Sprinter with a suitable donor at a local parts yard, but it's already raised up onto jacks. All the descriptions I've read have that you have to remove the front and rear bolts from BOTH left and right spring clamp plates nuts before the van is raised. Has anyone come across a workaround for removing those bolts? Trying to save myself a couple hundred dollars.

Thanks
 

Zundfolge

Always learning...
The only workaround is that you'd have to cut the bolts, which would be kinda challenging. Or I suppose you could bring two bottle jacks and get under the ball joints and lift the LCA's up again, but some yards have rules against using certain tools. Honestly I'd just pony up the $250 (you'll need the new rubber bushings to accompany the new spring), then you have a known good spring going in. Let me assure you you only want to tackle this job once.

Unless you have a thing for masochism...
 

Midwestdrifter

Engineer In Residence
I believe you can do the job with the van jacked. There will be some load on the control arms, but not too much to work around.
 

220629

Well-known member
... Honestly I'd just pony up the $250 (you'll need the new rubber bushings to accompany the new spring), then you have a known good spring going in. Let me assure you you only want to tackle this job once.

Unless you have a thing for masochism...
Given the effort required for removal and the possibility that the scrapyard spring may be faulty (eventually), I'd agree FWIW. Not to mention the risk of injury while working in a yard. Get a new part.

:2cents: vic
 
Thanks for the write up. I just finished the job. I had a cracked leaf spring and it was missing the driver side lower bushing. Used your method without any issues.


Sent from my iPhone using Tapatalk
 

Locdoc

New member
looking at a steel replacement, with the view to raise it back to a normal running height (probably 50mm higher than it is at the moment, riding on bump stops)
 

Midwestdrifter

Engineer In Residence
Whats your front axle load? If its not overloaded, a new composite or metal spring will bring you back to normal ride height. Both the metal and composite versions are about the same rate. If you are overloaded, such as a Class C with overhang, then you can opt for an aftermarket high load steel spring.
 

rjz5400

Member
Does anyone have part numbers for the bumpers,pads, and tie rod ends? I've never had a front sway bar (3500) so I can't compare old and new. Not sure which pad is driver's or which end is up on tre

One tre has a white mark on it, this all came from eurosd (accept the spring caps and sway bar was from a junk parts van)
 

rjz5400

Member
I got the numbers from europarts for the sway bar links, it also said the shirt pad I have is the driver's side? Doesn't make sense to me but .....


Also who makes bolts 18mm??? I have sockets but not wrenches for 18mm

So far can't get past step one, my spring is so flat there is nearly no room and certainly not for any straight tool to fit in there. {moment of weakness, came back later on and got my smallest crescent wrench in there, about a 4 inch long tool } (that's what he said)
 
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Locdoc

New member
Whats your front axle load? If its not overloaded, a new composite or metal spring will bring you back to normal ride height. Both the metal and composite versions are about the same rate. If you are overloaded, such as a Class C with overhang, then you can opt for an aftermarket high load steel spring.
About 1700kgs, equal weight to rear give/take 100kg and where can you get such? Happy to import to australia
 

Midwestdrifter

Engineer In Residence
1.7 ton is not too far off you max axle weight isn't it?

I would need to do a web search, but there was a vendor offering them a few years back in the states.
 

stutz

Tinkering Expert
Thanks Zundfolge for the write up. You saved me tons of time. Great job.

I just finished dropping out the crappy fiberglass spring and would had the new one back in if not for the upper rubber bushings that I didn't have and needed to change before finishing the job.

Thanks again,
Ron
 

kkanuck

LUV my T1N
Thanks Zundfolge for the write up. You saved me tons of time. Great job.

I just finished dropping out the crappy fiberglass spring and would had the new one back in if not for the upper rubber bushings that I didn't have and needed to change before finishing the job.

Thanks again,
Ron
Did you see a physical crack or split in it once removed? I will be tackling this job soon as well, I have all the parts including the rubber bushings you mentioned. Do you plan on getting an alignment or do you think you will be able to get it back to where it was once reassembled?
 

stutz

Tinkering Expert
Did you see a physical crack or split in it once removed? I will be tackling this job soon as well, I have all the parts including the rubber bushings you mentioned. Do you plan on getting an alignment or do you think you will be able to get it back to where it was once reassembled?
kkanuck

I didn't see a crack but I didn't look real hard either. The reason I decided to change my spring was because there was no space between the snub bumpers and the stops. The fiber glass spring weighed about 5 lbs vs 50lbs for the new HD metal spring.

My son and I had the old spring out and on the ground in just over 2 hrs. If you follow the above procedure you shouldn't have any problems. As a side note, I highly recommend having a good impact wrench (I have the 1400ft-lbs Milwaukee) for this job.
I do plan on getting a alignment after I am done but just because I believe that the van will be setting at a different angle then before (or at least hope it will be).

Regards,
Ron
 
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stutz

Tinkering Expert
Okay,

Just finished my front transverse spring replacement.

The new steel spring gave me about 1.5" more height - I think this would have been about the height when the rig was new. The overall job wasn't nearly as hard as the shop that quoted me $3500 made it sound. Removal was 2 hours. Installation was 4hrs.
Note this was two people with a good impact wrench (a must).

I would like to add a step to the Zundfolge write up. Before I started the installation, I glued (with some good silicone) the upper and lower mounts to their respective seats to keep them moving around and prevent all the swearing that Zundfolge refered to during the seating of the spring step. I didn't try it the other way, but I could imagine that the rubber pieces would be hard to keep in the right place while trying to lift the spring in to its slot.

20210311_091154.jpg
Note: The red seat goes on the right side with the taller lower seat. I brought them in the house overnight and let the silicone set up good before starting the installation.

Hope this helps.
Ron
 

kkanuck

LUV my T1N
Okay,

Just finished my front transverse spring replacement.

The new steel spring gave me about 1.5" more height - I think this would have been about the height when the rig was new. The overall job wasn't nearly as hard as the shop that quoted me $3500 made it sound. Removal was 2 hours. Installation was 4hrs.
Note this was two people with a good impact wrench (a must).

I would like to add a step to the Zundfolge write up. Before I started the installation, I glued (with some good silicone) the upper and lower mounts to their respective seats to keep them moving around and prevent all the swearing that Zundfolge refered to during the seating of the spring step. I didn't try it the other way, but I could imagine that the rubber pieces would be hard to keep in the right place while trying to lift the spring in to its slot.

View attachment 174540
Note: The red seat goes on the right side with the taller lower seat. I brought them in the house overnight and let the silicone set up good before starting the installation.

Hope this helps.
Ron
Great Tip Ron,


Is that red seat you siliconed the new mounts to right side already painted red, by the factory, or you painted so you know which side is which?

You siliconed all 4 seats from the looks of it, 2 lower to the metal plate and 2 to the upper, so I will try your method soon when I jump into this project, thank you!
 

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