LUVTruck.com

phpBBV3 Message Board
It is currently Tue Aug 14, 2018 9:10 am

All times are UTC - 6 hours




Post new topic Reply to topic  [ 4 posts ] 
Author Message
PostPosted: Fri Mar 14, 2014 4:42 pm 
Offline
Member

Joined: Thu Oct 31, 2013 4:00 pm
Posts: 31
Location: Corrales, New Mexcio
Brothers/Sisters of the Diesel world: Alas, I dropped my rear axle assemble, locked it on a bench, and disassembled this unit, removing the bearings on the pinion shaft with some extreme difficulty. Turned the mic work over to a seasoned wrench and viola!

We discovered that the bearing (front) close to the pinion nut was positioned 20% on solid steel circumference, while 80% was on the spline area...not ever seen by my wrench. Out of round pushing .006 to .008" meaning that if one were to rework the shaft (build up, machine/lathe, then heat treat)...more money than it's worth. I need another pinon shaft for sure!

Wondered if the factory authorized assembly plant had placed a pinion shaft "incorrectly machined" with the splines longer than original specs...ideas on this issue?

We did a "cost benefit ratio" looking at a used pinion/ring set, new bearings all around, including axle shafts, new seals and then just the bearings for the pinion shaft: Over $300 on a very good day, for sure!

Up popped the idea "why not just swap out another rear axle assembly and spend $200?" (If lucky, that is.)

Next question: With a present axle ratio of 3.73, would a 3.42, even a 3.23 cause headaches in daily driving in urban areas (stop and go)? Would such ratios work fine on highway/interstate driving and passing cars? Naturally if working ok, could one expect gas mileage (one of the primary reasons I accepted this ride) rise even beyond what the limited city driving (350miles) prior to axle removal suggested was at 33 plus miles per gallon?

Of note: Does an 80 or 79 Chevy Luv with automatic trans come with a 3.73 axle ratio and slip right into my 81 with no modifications (emergency brake system, etc.)? What years of S-10s will work if at all?

Are there models of Isuzu that would have a "direct swap in" rear axle assembly? I spotted one Isuzu with disc brakes on the rear at a local salvage yard prior to knowing I might need a complete assemble...the width is important for sure, we can modify the brake system to accept discs on the rear via valving.

I note from my research that the axle codes (GM) are: GT4=3.73 GQ1=3.73 GU5=3.23 GU6=3.42 G80=posi/limtslip and the codes are supposed to be in the glove box on S-10s etc. As to where on the Isuzu, I'll have to learn or be informed by a member....like my sun visor mentor Joe Isuzu...if time permits and you are willing to do so. I also might need that person's number who you know carries the used ring sets, although my wrench is concerned over other's micrometer skills and veracity.

What a bummer, but at least I discovered what the whining sound was and it occurred at home--in a garage, under my conditions, not on the road out of town, etc.

What a fun vehicle to drive, my very first diesel and a little truck to boot! All I need now is a decent radio to replace the original AM luv model (by fugitsu I think). Got the seat re done in heavy cloth, maroon with black trim...sweet!

Would prefer a set of black or maroon seat belts if you have such and wish to sell...my check to Joe Isuzu must have cleared, no word it didn't from him.

Found original rims, got them blasted and painted with new tires with alignment. Discovered the shocks (original I suspect) were shot all around (who would have guessed this reality?). Have the rear tail pipe ready to install, will be acquiring a Gates timing belt plus that oil line to the alternator (if I can't find this locally, then here comes another request to Joe Isuzu for the name of his contact again).

The .22 shell casing fell off the little spring...I'll try a spring from a ball point pen next. Cleaned the contacts on the wiper switch and now waiting for rain...system works great!

Haven't had this much fun since the IRS knocked on my door!

Again, thanks for the previous help and any ideas, suggestions and information you can and wish to provide.

Bob


Top
 Profile  
Reply with quote  
PostPosted: Mon Mar 17, 2014 12:37 pm 
Offline
Member

Joined: Thu Oct 31, 2013 4:00 pm
Posts: 31
Location: Corrales, New Mexcio
Update on 81 axle swap: Ok, went to a junk yard looking at numerous S-10s, S-15s etc after year 1984. Not good news for me: Five lugs, not six...axle to axle greater than 54", when I think my original unit read 53" along with not being able to come up with a 3.73 unit except on S-15 that had the GT1 axle code in the glove box, an 88 year model. Would also have to rework emergency brake cable system.

However, lo and behold I found the '81 Luv sitting in the line. Short bed with a four speed and gas engine...with rear axle assembly totally intact. Serial number J8ZBL14NXB8211327.

I don't think one can tell from the vin what the axle ratio would be. Perhaps it being a simple gas short bed with four speed would give one a 3.42 ratio...hopefully not a 3.23. I tried rotating the driver's side axle to see if I could figure out the turns etc. of the driveshaft. Passenger side had rim and tire still on and would not spin as I turned the left axle.

And yet, these gears would work, would they not? It would just be somewhat slower going up from first through the gears, or one would spend more time in a gear getting up to speed before changing to the next gear?

In other words, this rear end looks really clean, low mileage even though the odometer is missing (looking at the rest of the vehicle's condition along with the under-body, lack of grease, oil etc. spread around) it would seem a chance swap might just make simple sense.

Unless somebody has a good, straight pinion shaft and matching ring gear for sale. Recall my main concern: the splines on the pinion (of my unit) were long in that the front bearing was "set" 80% over this area with the 20% on round shaft...leading me to believe that the milling of this part was inaccurate in spline length, yet allowed to go into a unit nonetheless.

Thus, if you've got the correct parts (3.73), I've got the monies. I intend to move fast on this issue because I want to drive my diesel...spring is here!

Note: If the 3.42 or 3.23 rear axle ratios will make my diesel run like an old turtle please tell me now before I again choose to cut my hands etc. in taking out this used unit I found. I am no longer a speed demon, youth has long since passed me by, I drive like an old geezer who gawks going down the road at nicer vehicles passing mine.

Thanks for your help and advice in advance. I am having fun putting this vehicle on the road.

Bob


Top
 Profile  
Reply with quote  
PostPosted: Mon Mar 17, 2014 1:46 pm 
Offline
Addicted to LUV
User avatar

Joined: Tue Sep 13, 2005 7:54 am
Posts: 1508
Location: Germantown, TN (right next to ElvisTown)
Bob,

I've been on the road, so I didn't have much time for forums. For most 5-speed diesel LUV/P'up owners, the 3.73 is the optimum rear end. Those came ONLY in diesel LUVs and P'ups that had 5-speed transmissions. That 4-speed gas LUV you're looking at should be a 3.41. Some owners have done this swap, and they like it. I don't recommend it unless your engine is still strong, and you live in a really flat area. Otherwise, you won't have the power for 5th. And, if you ever upgrade to the '86-'95 gas transmission, it has higher gears in 1st, 2nd, and 3rd--so a 3.41 would make it even slower off the line.

You only have 3 bolt-in choices: 3.41, 3.73, and 4.10. In the 2nd-gen LUV and all P'ups, the 3.41 was in 2wd 4-speeds, gas and diesel. The 3.73 was only 5-speed diesels. The 4.10 was in gas 5-speeds, all automatics (gas and diesel), and all 4wd trucks (gas and diesel). You do NOT need the whole axle, but the axles have to come out to remove the chunk.

If you want a 3.73, contact sqdeb@yahoo.com. They just might have one. I got mine from them, and it was very reasonable. They're great people.

Jack

_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.com
IsuzuPup.com


Top
 Profile  
Reply with quote  
PostPosted: Mon Mar 17, 2014 7:57 pm 
Offline
Addicted to LUV
User avatar

Joined: Tue Sep 13, 2005 7:54 am
Posts: 1508
Location: Germantown, TN (right next to ElvisTown)
JoeIsuzu wrote:
You only have 3 bolt-in choices: 3.41, 3.73, and 4.10. In the 2nd-gen LUV and all P'ups, the 3.41 was in 2wd 4-speeds, gas and diesel. The 3.73 was only 5-speed diesels. The 4.10 was in gas 5-speeds, all automatics (gas and diesel), and all 4wd trucks (gas and diesel). You do NOT need the whole axle, but the axles have to come out to remove the chunk.

Minor correction: The 1st-generation Impulse 3.90 rear ends will also work (just the chunk, not the whole axle).

Jack

_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.com
IsuzuPup.com


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4 posts ] 

All times are UTC - 6 hours


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group