[4x4addict]

Hi Folks,

I am trying to source an NGCS chasis for my next project. However, if I cannot get one in a reasonable time, I would like to strengthen my current MM540 chasis & change the leaf perch to use the wider leaf springs from the NGCS chasis.

I am planning to make another C and box the chasis and some additional cross members.

I would like to hear from you guys about pros and cons and anything else I should keep in mind when doing this.

The reason I am doing this is that my jeep is getting a heart transplant with an 125bhp/28kgm Isuzu 3.1L TCIC IDI engine.

[pjbiju]

One of the easier methods used with good results is to add another C-section (either outside or inside) to improve the strength of the chassis. In this case, you have to add the additional C inside. Adding it to the outside could alter the mounting positions of other brackets on the frame. And if those brackets are welded onto the frame, then adding an outside C-section would be impossible.

This can be done for the whole chassis or at certain points and the edges can be welded together.

Unlike some of the truck chassis where you have straight long members for the chassis frame, the long members of the chassis of Jeeps are not straight. I guess even the cross sections would vary across its length. That would make it difficult to convert it into a box section or even a full length C over C. Also if you weld in other places other than the free edges, it could lead to weak spots in the frame.

I do not think you need additional cross members. But strengthening existing ones could be thought of.

[jeepster]

its very complected to add another c section & making it Box section.

IMO best way to increase torsional rigidity is to add cross-members to c section chassis.

see attached pic's.

http://www.team-bhp.com/forum/4x4-te...tml#post835143

rgds,
Nikhil

[Tejas@perioimpl]

Interesting. I'm gonna keep an eye on this thread. I too need answers.

[Kandisa]

Originally Posted by 4x4addict

..I am trying to source an NGCS chasis for my next project. However, if I cannot get one in a reasonable time, I would like to strengthen my current MM540 chasis & change the leaf perch to use the wider leaf springs from the NGCS chasis.

Nice thread. I am sure the idea is running in many jeeper's head. Putting another C section might not be very complicated. But i wonder how easy it would be to change the leaf perches to use the NGCS leafs. Has anybody done this?

[Sudarshan]

Very common things to take care with chassis repair .( before the work starts )

I am no expert but the things I am listing must be looked into detail with the help of persons having expertise in that particular/respective field.

I have listed this , thinking as if I am going to do it .

1) objective ( clarity ), what exactly you want

a) repair ?
b) modification ? major/ minor
c) re construction ? total/partial

2) design of components , ( general layout ) also accurate measurements

3) need of jigs ,fixtures etc if any ( tools etc ) OR in your case choice of workshop & person

4) choice of material ,( metal ,grade ,properties etc ) from where to source it

5) choice of welding
a) which type of welding will be the best & who can do it (welding methods )
b ) choice of welding machine & material ( type of rods,its quality etc)

6) anti rust treatment ( cleaning of chassis, paint or galvanising )

Sudarshan

[Sudarshan]

This is a little OT

This (chassis strength & others ) is the exact reason for the birth of the Land Rover .Its born ( & inspired ) out of WW 2 Jeep only .

After WW2 British engineers experimented on few Jeep chassis ( war surplus ) . They wanted a way out from the shortcomings of the Legendary Jeep. So they experimented ( chopp-shop type )

One major part they looked into is the C section chassis .The Jeep chassis has its few disadvantages/limitations . In simple words its not suitable for longer wheel base then the 80" original & there is a need for more strength if more powerful motor is given .

look at the both pics & compare , the Rover chassis has more cross members then the Jeep & its box shape . This gives more torsional rigidity ,that improves handling

Jeep chassis ( 80" W. B. )



Land Rover ( series ) ( 88" W. B.) Have a look at the fixed cross members bellow engine bell housing & GB shown in red arrows



Land Rover ( 109" W. B. ) chassis drawing ( note the number of cross members)



Sudarshan

[Grace]

Wow, an interesting topic I must say. Lemme introduce myself, a new kid on the block, Am Andy, known as Grace on this forum. I recently (March 2010) bought an 540 just to offroad. My other ride is a pickup 4X4 and I wanted something easy to go around. Went searching within Bangalore and came up with a find from a known jeeper. I was very ecstatic with the find that I closed my all senses and just went bling bling and paid him and took the ride home, little to realise that there were a lot of issues to be dealt with. Now since this a chassis rebuild story,will post my 'dukh bhari dastan' in appropriate thread. At this point I would like to thank 4x4addict with whom I had a brief chat before I took up this work. I will let the pictures do the talking and please be assured that pictures are in the right order. Your comments and suggestions are welcomed.

oops .. posting pictures for first time, do bear with me

[Grace]

Mods may delete if duplication of photos are happening. Regret I am too young on this forum

[jyobeb]

Nice work Andy! The problem here may be the addition of so much weight added to the chassis. May have been simpler to get another chassis.

[Grace]

Hi Beboy,

Addition in weight is just 16 kgs. But benefit of strength derived is in manifolds.


OT: Hope you remember me,I met you in Madurai with Raghuram at the Toyota showroom,BTW thanks again for the snorkel,it is intended for this Jeep. I heard from Tini that you swapped your engine,hows the jeep now? Rocking ... I suppose

[Sudarshan]

@ Grace , looks good , now peace of mind . its good to work on a completely stripped down chassis as welding can be done properly .

& hey you certainly don't sound like a new 'kid'


BTW how did you choose the material for the job ? any specific grade of steel ?

Also have you checked the chassis after the job for any misalignment ? & how ?

Sudarshan
P.S. @ jyobeb, new chassis ok but how much it will cost ? I think this is cheaper .

[jeepster]

hey Andy , great work bro.

how could a so called Jeeper sell this to any one!! (i hope he is not a bhpian here)

can you please share the costs.


rgds,
Nikhil

[Grace]

@jyobeb, cost of new chassis (as offered to me by the mechanic was at RS 20000), this would entail registration in the RC book, plus other costs such as body bushes and additional labor which would've easily cost another5-6k. Getting jeep done at reputed mechanic in Bangalore is a costly affair (good ones are hard to come by). Note that I am on a shoestring budget. Wait till you hear the cost for this mod job.

@Sudarshan sir, Thankyou for the encouragement received ,I am a new kid, with respect to the questions posed by you. I went around hunting in the gujri market for chassis grade steel. Did not bother about thickness but was worried on the final added weight. I found that truck chassis (all sizes) were getting scrapped and decided to get those chassis parts welded onto the jeep chassis. Continued search lead me to lot of folks who strongly advised against going in for truck chassis welding on jeep chassis. More so on welding remaining on the chassis and adding of weight. I finally decided to go in for 4mm by 2.5 inch by entire length both sides up and down as that was the cheapest option. As regards the alignment, checked with a spirit leveler (I know it is not a very accurate tool for this activity) and trust in the mechanic's ability as he is the most famous in Bangalore.

@jeepster, thankyou bro for your kind words,the person who sold the jeep happens to be a member here.

Cost Involved: Removing and putting back entire body and engine and all other parts from the chassis: INR 4000.

Cost of grinding the burrs (please read as previous ugly welding job): INR 500

Cost of MS FLAT 4mmX2.4 inchesX10 feet X4 pieces(there was wastage too): INR 2000 odd.

Cost of MS flat cutting,shaping,hammering,Riveting and welding 4 pieces: INR 3000.(This is a labor intensive job)

cost of Brake oil : INR 300 odd.

Removing and reinstallation of electrical work : INR 700.

Sundry expenses like replacement of Engine bedding,body bushes and other: INR 800.

Piece of mind : PRICELESS

This done, now I have the confidence of doing the toughest of Bangalore OTR spots. My next round of mod is installation of MRCBT steering. Depending on 4X4addict. Ahoy !! are ya listening?

Warm Regards

[swastikviji]

Hi Andy
This is not just strengthening chassis, it seems you are rebuilding whole chassis, any how i am sorry for you for not inspecting the jeep before you buy.