76 king cab 620 4x4 build theories and considerations

[76*620]

Hello,

So obviously you all know I am new to registering to this forum, I have built a few z's and used this site as a resource for years never feeling the need to register since things are covered so well in the posts. I have recently acquired a 620 king cab and have kinda decided on a 4x build for it. Since it is winter I am in the planning stages. initially I was thinking of an sr swap but the 4x idea has bit hard. The motor is a question debating between a tdi or ka but everytime I think of these engines  and the transmissions I would like to use there are issues that lead me to the v8 as a simple solution. I would like to use a 200r4 or 700r4 backed by a np205 transfer case. Right now I have a 93 jeep grand cherokee in the yard and it seems like a seems like a simple enough job to take the four corner coil suspension and axles out to place on the datsun. I have not taken measurements or anything on it yet but I see little visual difference saying dont do it. I will post some pics of  the truck in a bit, until then I am going to post what little work gets done and any ideas I have here.

[mikeanike99]

Welcome and I hope your project goes well

[datzenmike]

V8 don't fit at all in a 620, although a better chance in a raised 4x4. The firewall has to be cut out and you'll loose your heater. What about a newer 4.3 V6. Tons of power and good fitment.

[jrock4224]

red eye has a 620 4x4 that kicks ass and is ka powered i believe

[]2eDeYe]

DO you plan to go 4 wheeling? If so I would look for a stronger set of axles than what is in that Cherokee. V8's are fun but I went from 8mpg in my CJ to 24ish in my KA 620, still fun costs less per grin.    :)

 

Edit, thanks for that Jrock :)

[76*620]

Besides being a v8 the firewall cutting makes me nervous. The KA I am betting will end up being the answer. I have to have an auto though, Bad left side of my body from the Army, clutches start to hurt pretty bad. I really like the tdi but there seems to be few options for the trans; the transfer case won't matter because it is going to be a divorced unit. Primarily the trucks use will be DD duties however a good strong 4x is needed to get to my hunting and fishing locations. Every conversion I have seen uses leafs is this due to cost and simplicity or another issue I have not yet seen, I would really like coil front I can work with a 8.8 rear or a shortened 9inch. I need a 33 min tire but feel better about 35" on the trails I travel. I just can't shake the tdi though, I love my diesels and one in a datto would be fantastic. Anyone have first hand knowledge on the tdi samurai swaps? I know nothing about the sammis but I do know they frequently get tdi's.

[jrock4224]

i got a dohc ka automatic tranny i will donate should u need it ...i too have visions of a straight axle 521 with a tdi in my mind....i dont blame u there cool little motors..

[]2eDeYe]

I did leaves due to cost, they were already in my garage. If I had money to spend it would have went 3 link and coil overs   :)

 

You should be able to get newer auto from a Nissan 4x4 attached to a KA and a transfer case.  One thing to keep in mind is the side the transfer case output for the front axle.

 

I don't have firsthand TDI info but they seem to be a fairly easy swap. You might consider a Toyota transmission/transfer case behind that as it is a well documented option and you could run a Marlin Crawler setup later on.
 

[jrock4224]

awwww shheeeeeettttttt its getting serious in here

[76*620]

New question, I have spent the last couple days researching ka motors. what I have found is the ka in the Altima and 240sx have different block castings that are stronger than the others. apparently this has something to do with two different manufacturing locations. The question is can I take an Altima motor which is mounted east west and use it in the north south configuration? of course the trans will be different but will the motor change mounting directions?

[]2eDeYe]

It's possible, but a giant pain in the ass. The block on the RWD KA is plenty strong, I haven't heard of anyone breaking one.  :)

 

P.S.  All the KA blocks have different castings, the 240 and Truck blocks are different as well and use a different pan/sump configuration. The 240 is front sump and the truck is rear sump. Either one will work better in a RWD configuration than the Altima KA block.

[OneFreakyMF]

I'm swapping a 4.3 into a 620. It's a tight fit! Have to trim the core sport to get the radiator in. I'm going to have to make my own exhaust manifolds. If you are going to end up wheeling your rig hard you'll want stronger axles but for DD and light trail use the D30/35's will work fine.

 

Leafs are a lot easier and cheaper to install. Although, build like this are never easy in a Datsun! Damn near everything need to be custom made...

 

If I was to start over I'd go with a four popper. Save yourself a lot of headaches! Gear the axles to run 35s and you'll be set!!

[Boxcar]

At best, the Grand Cherokee is a poor choice as a donor for a 620 conversion.

 The Dana 35 rear axle is probably the worst axle that Dana ever produced.

 While it can be supplanted with an 8.8 from an Explorer  you will still be dealing with the infamous Vack lock 30 up front.

The Dana 30 Vack lock is not a horrible axle, it won't handle a 35" tire. And , due to the fact that it runs the 2 pc Vac lock axle, will be problematic with 33's.

I'd recomend Dana 44's from a Wagoneer. Or 1st generation Toyota axles.

 The suspension system for the Grand is one of the most expensive to modify that I have seen, and is week at best.

As mentioned earlier the V-8 is a big job.  The frame of a 620 was never designed for the 600+ pound power plant and the squeeze is really an issue.

 You can go with a 215 Buick V-8 Or a Rover ( Much smaller and lighter than any other V-8 option.) Support is sketchy and parts are expensive.

A good KA swap will net the same or similar HP & torque #.

A 700R4 and 205 combo is near bullet proof BUT it's huge. And tight fit.

I use the Dana 20's or 18's for that very reason.

 Decide on the drop ( passenger or driver )  Then plan you're build around that format.

As to lief vs coil.

If you are building a dual purpose rig ( DD & Trail ) lief is a much simpler system . A 4 link takes mad math and fab skills to accomplish successfully.

 

Anyone have first hand knowledge on the tdi samurai swaps? I know nothing about the sammis but I do know they frequently get tdi's.

 

Just a bit.

 

 

I have built just a few........ While the TDI is a good conversion for a 2500 lb Samurai as long as you're in no hurry,  Not great in a 4000 lb Datsun 620 4x4.

 

 

 

 Hope this helps.

[76*620]

The only reason I was thinking the grand cherokee is I have one sitting in my driveway that I just dont drive and the appeal of every part I need being in one place is huge. The axles are admittedly not the best, but contrary to internet opinion they handle 35's fine both on the highway at 85 and on the trail, I had zero issues for hunting season or on my fishing expeditions this summer. Is an engine swap and 4x conversion going to add 1700 lbs? I had assumed 500 ish on the heavy side. Maybe a 97 jeep sahara will be a better option, I can get one for 200 as a roller and it has a dana 44 rear so it would leave me with finding a front to work with. I think it was the 2001 jeep that offered a coil d44 front.

[GRpufnstuf]

And I think the 44 only came on the Rubi

[Boxcar]

And it's not a true 44 . Check the parts interchange to the Standard 44.

 

You will be  adding nearly 500 lbs in wheels and tires alone. ( 5 - 35" tires on 8" steel rims)

By the time you are done converting a 620 into a proper 4x4 you will be at 4000 lbs. WET. 

 

 

 

 

 

 

 I'm not quoting Internet opinion on the Dana 35 . I'm a builder. I speak from exp.

.

While I have never riped up a 97 TJ to build a 620, you will still have all of the same issues as the GC.

D-30 front Vack lock / D-35 rear and a very expensive lift option.

 

If the TJ you mention has a 44 in the rear , It's been modified ( for the better ) .

 

 You'd be better off using a  CJ7 as a donor .

Dana 30 manual lock 1pc axles / Dana 44 (early ) or AMC 20 rear ( convert to clip-less 1 pc axles )

A Dana 20 or Dana 300 ( if a late model ) T-case.

Saginaw power steering.

A usable column.

ETC. ETC. ETC.

All in a passenger side drop format.

And best of all very, simple wiring.

 

If you are determined to build a 3 or 4 link suspension system for the 620 . Build from scratch.

The components from the GC  or TJ are week at best ( stamped steel ) and to short to turn 35" tires under a 620 without MAJOR sheet metal mods.

 

I'm not trying to rip on you're idea, or piss you off here. Just trying to save you money , time, and head ach.......

[]2eDeYe]

 

 

If the TJ you mention has a 44 in the rear , It's been modified ( for the better ) .

 

 

Actually you could get the TJ with a Dana 44 rear as an option from the factory. My buddy bought his new with a factory Dana 44 rear.

[Boxcar]

Yea. But not in 97.

[76*620]

The Sahara had an option for the d40, at least that is my understanding? I have not visually verified it, it is an acquaintance that has it  and mentioned it to me. He is a gomer so could totally be wrong. I like coils, but from what I am gathering I will buy the cj stuff and run leafs for a while. 

 

And it's not a true 44 . Check the parts interchange to the Standard 44.

 

You will be  adding nearly 500 lbs in wheels and tires alone. ( 5 - 35" tires on 8" steel rims)

By the time you are done converting a 620 into a proper 4x4 you will be at 4000 lbs. WET. 

 

 

 

 

 

 

 I'm not quoting Internet opinion on the Dana 35 . I'm a builder. I speak from exp.

.

While I have never riped up a 97 TJ to build a 620, you will still have all of the same issues as the GC.

D-30 front Vack lock / D-35 rear and a very expensive lift option.

 

If the TJ you mention has a 44 in the rear , It's been modified ( for the better ) .

 

 You'd be better off using a  CJ7 as a donor .

Dana 30 manual lock 1pc axles / Dana 44 (early ) or AMC 20 rear ( convert to clip-less 1 pc axles )

A Dana 20 or Dana 300 ( if a late model ) T-case.

Saginaw power steering.

A usable column.

ETC. ETC. ETC.

All in a passenger side drop format.

And best of all very, simple wiring.

 

If you are determined to build a 3 or 4 link suspension system for the 620 . Build from scratch.

The components from the GC  or TJ are week at best ( stamped steel ) and to short to turn 35" tires under a 620 without MAJOR sheet metal mods.

 

I'm not trying to rip on you're idea, or piss you off here. Just trying to save you money , time, and head ach.......

I am not easily offended and obviously you have more knowledge and experience than I, so I can not argue.

 

Just for knowledge's sake how would you Boxcar go about a 3 link setup on a 620? My concerns with self fabrication is angles geometry and such, that is why I thought a take out would be the best solution. I know those are super important on my stock car. I also figured worst case scenario I upgrade axles later.

[76*620]

Box car, Am I to understand you recommend the the engine, trans, transfer case, axles, and everything for the swap or are you suggesting just the springs down? 

[Boxcar]

Everything but the engine and transmission is usable in one form or another for the swap in question. That is if you use a CJ7 or 73 R newer CJ5 as a donor.

 As to the 3 or 4 link question , I'd have to measure my frame and do some calculations and design work before I would answer that question.

[JNHEscher]

Dunno if this is against any forum rules here, but my friend has a complete ka with auto from his 98 240 for sale. It runs without any issues, and is cheap.

 

4 links can be done cheap if you stick with welded bushings instead of threaded rod ends. Pre-fabbed brackets add up real fast, but there's a lot that you could use off the Cherokee.

[76*620]

Alright sorry I have been busy so.... I have aqcuired a wagoneer d44 front axle and a 1991 chevy s10 donor vehicle, I am also planning to use toyota springs unless there is a better suggestion.

[76*620]

https://www.allprooffroad.com/pickupsuspension/pickupleafsprings

https://www.allprooffroad.com/pickupsuspension/spring-hanger/41

https://www.allprooffroad.com/pickupsuspension/pickupshockhoops

 

So these are the parts I have Ordered to instal the d44 on the front. On the spring page I went with a 4 inch lift long travel spring. I am not sure if the shock hoops will work or not but with a little adjustment I am sure I can fix any issues.

[76*620]

Are ther options for a rear axle that I would not have to cut other than D44 as I am having trouble finding one for a price I am willing to pay.