Team-BHP - Is Independent Front Suspension (IFS) good for offroading?

Continuing from here: http://www.team-bhp.com/forum/4x4-of...ml#post1109747

Quote:

Originally Posted by vinod_nookala (Post 1109747)

4x4 addict,
The striker in the pic as you rightly identified has an IFS with 4wd. This is the same suspension set up used on scorpio. I read it in a auto magazine that even in new Bolero CRDe the front suspension is that of Scorpio type and there has been a merge of scorpio front end chassis architecture with the original tubular design of bolero chassis.

I have seen IFS with 4wd combination on export bolero pickup models. Iam sure the same is the case with striker in the picture. Also i suppose the Bolero CRDe when offered in 4wd will do away with the rigid axle set up as the the new chassis can offer 4wd with IFS upfront.

I have heard that IFS is almost useless for the kind of offroading we do in India, I know many who are totally against IFS. So is it wise to have IFS if Mahindra does come with a new MM540 version?

Quote:

Originally Posted by Spitfire (Post 1118198)

PS: Dont make it butt ugly though, my wife has a say in the money being spend.

LOL my friend!

Quote:

Originally Posted by Samurai (Post 1170054)

I have heard that IFS is almost useless for the kind of offroading we do in India, I know many who are totally against IFS. So is it wise to have IFS if Mahindra does come with a new MM540 version?

IFS will increase the cost.

Quote:

Originally Posted by Samurai (Post 1170054)

Thanks Spitfire for bumping this up.

I have heard that IFS is almost useless for the kind of offroading we do in India, I know many who are totally against IFS. So is it wise to have IFS if Mahindra does come with a new MM540 version?

Samurai,

I agree that IFS is not as competent live axle off road for articulation reasons. However, increased power needs better handling chassis including suspension. Also the CRDe engine being very large there could be issues of oil pan touching the front axle. IFS houses the larger power train easily. IFS gives better on road handling considering a CRde MM550 can do about 140 kmph with ease. For off road if front IFS is matched properly to rear long travel leaf just like in a bolero i guess it can manage most of the terrain!!

I agree on the point that when transversing a rocky terrain one must be more careful and will not be a carefree scrape and drive situation like in solid live axle!

dear Sharath / Vinod,

The maximum speed the jeeps actually do is on average is 100Kmph on the solid live axle, but when it comes to the hard core offroading this where the major issue will rise, & no way one can repair the suspension at the site,

Secondly once in the water it will surely be an issue, & one will have to rush to the center for a ful service of the IFS,

Yes IFS is great on hard tarmac & on a simple trail, but not on the kind of trails where we have taken our jeeps,

For the IFS you need to have a hard base once it is stuck & trust me there's nothing one can do, all you will need is help,

Check out the wrangler even they have Solid live axle, with coil,

Well I am sure moving back the Engine by a few inches should solve the issue,

Finally one needs to push this model to the limits to understand the requirement of an offroader,

Best regards
Vinay thomas
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Quote:

Originally Posted by vinod_nookala (Post 1170151)

Create a special vehicles division and allow the 550 to be customised indefinitely. On the aesthetics front your military spec 550 looks a million dollars!

Offer the customer choice to order:

Solid axles with leaf spring setup
Diff locks front and rear
High lift kit
Rock crawl gear set
Choice in axles
Mud or rock crawl tyres
Skid plates and rails
Roll bars

all, obviously at a price.

Your standard 550 for civilian use should be offered in 2wd and 4wd in attractive colours
spartan but attractive weather resistant uphostery
power steering
IFS
AT Radials
diff setup that allows a 150 kmph top highway speed

The standard 550 with 4wd shouldn't cross 5.5 lacs

The offroad package could be offered for 1.5 to 2 lacs depending on what's ordered

Quote:

Originally Posted by vinod_nookala (Post 1170151)

Samurai,

Also the CRDe engine being very large there could be issues of oil pan touching the front axle. IFS houses the larger power train easily. IFS gives better on road handling considering a CRde MM550 can do about 140 kmph with ease.

Excellent point, Nook. The military likes IFI because it allows them to have a lower silhouette and makes a vehicle that much harder to hit. Stacking the motor on top of an axle increases height.

The Americans had a fine jeep in the 70s and early 80s that had a V-8 in it. It was an absolute rocket on the straights. Unfortunately it was a mis-guided missle in the corners. The heavy V-8 sitting high over the front axle made it unstable in the corners or even taking big bumps at any speed. They had to take it off the market altogether because of the heavy incidence of roll-over and injury. Customers were toppling and sueing Jeep Corp en masse. IFi might have helped along with a little wider track.

Quote:

Originally Posted by vinod_nookala (Post 1170151)

How come REMM340 managed to fit a SZ2600 in a CJ340, without fouling the differential?

IFS gives better Road Handling, properly setup Solid Axle are quite close if not better, i.e Bolero 4WD.

To expect 140Kmph is good what happens on the corners you will have to brake hard to come down to 50-60Kmph.

Quote:

Originally Posted by ex670c (Post 1171367)

Hey arka,

We are talking about the same point. Soild axle can be quite close to IFS if tuned well, but will never match them in handling department. Further to optimise handling one has to compromise on ride quality like in bolero 4wd. I still feel coil over live axle set up like in defender and wrangler is the best option for a good off road performance with decent on- road handling. But such kind of set up is not available with M&M and hence extra cost to develope one.

On braking into a corner from 140kmph to 50-60 kmph, it surely is a risky thing not only for MM550 but for scorpio /safari kind of vehicles too. Since MM550 is not a top heavy vehicle, iam sure it will be better than the current scorpio:)

(p.s- Red mm may have done it, but i donot know if that was a straight fit. Since you know the Crde unit is pretty heavy & large, it could be placed with IFS set up for CG reasons. All bolero Crde pick up models abroad are offered with IFS 4wd set up and so does the new Bolero storm domestically)

Hi Vinod,

Solid Axle aside, the MM540 at High speeds is unstable because of the wheel-base.

The CG will be constant in a Solid-Axle vis-a-vis IFS vehicle as the IFS tends to dive at one side while cornering.

Could be that M&M is introducing, forcing IFS 4WD down our throats because..
1) Complicated to Service and Overhaul
2) No Local Mechanics can work on it..too many variable Caster/Camber/Toe-In.
3) Result is expensive support and service bills after every OTR clap:.
4) Obviously only M&M Garages can service these vehicles.

Conclusion - M&M is selling a vehicle which only they can service :D..do the maths.

Besides I heard the IFS -Bolero Camper was not very successful in South Africa, they preferred the Solid Axle Camper & Pikup Series.

Regards,

Arka

Quote:

Originally Posted by ex670c (Post 1173631)

Could be that M&M is introducing, forcing IFS 4WD down our throats because..
1) Complicated to Service and Overhaul
2) No Local Mechanics can work on it..too many variable Caster/Camber/Toe-In.
3) Result is expensive support and service bills after every OTR clap:.
4) Obviously only M&M Garages can service these vehicles.
Conclusion - M&M is selling a vehicle which only they can service :D..do the maths.

Hmmm...wonder what M&M has in mind exactly. I doubt if the unsophisticated M&M shops close to me could ever service an IFS.

Another nice thing about a standard front axle housing is that it is a massive piece of steel that protects the undercarriage somewhat from rocks, slush and lurking titanoboas.

Independent suspension is a very broad term. IS systems can be engineered to provide better axle articulation and GC than a rigid axle. The problem is that double wishbone IFS on most SUVs is designed with a road bias, so they end up with poor articulation and GC.

Some of the most capable offroad vehicles (Haflinger, Pinzgauer and Tatra) use IS for all wheels.

The clearance for my mm340 front axle relative to the oil pan is very tight, and I wish that I could push my front axle forward 6 inches. This would allow me to drop the motor about 2 inches and lower the vehicle COG and increase front axle travel.

IFS is good for a lot of reasons, including better handling, lower weight, lower cog, smoother ride, etc. This is the reason for many modern SUVs having 4 wheel IFS. IFS also allows for easier suspension packaging within the vehicle body.

Solid axles are just much tougher. They can survive much more abuse and higher payloads with almost no maintainence. Solid axles are just ideally suited for Indian driving conditions.

Quote:

Originally Posted by RedMM340 (Post 1173957)

IFS is good for a lot of reasons, including better handling, lower weight, lower cog, smoother ride, etc. This is the reason for many modern SUVs having 4 wheel IFS. IFS also allows for easier suspension packaging within the vehicle body.

Fully agree, but how does it help in offroading?

Any counter-arguments to Arka's points?