New Ring and Pinion Front and Rear

[BigRed40]

I recently had a bad day when I discovered that the bolts on the flange connecting my rear diff to my rear driveshaft were hand tight.... How I did not notice before hand is the question.. As I was so generously pulling out someone who was stuck pretty bad in some mud my 40 hopped a little and that was all she wrote.. The rear Pinion gear shattered and out fell my driveshaft. Long story short, I had to drive in reverse for about 45 minutes to get back to the parked trailer! I am going to get new gears front and rear. With 38.5" TSL's I was thinking about getting 4:88 or possibly 5:29. Any suggestions??

 

[sandrat62]

My friend I feel your pain. I have 38 TSL also and exploded my ring and pinion out in the dunes. But unlike you I had to be towed out backwards to my trailer because my rear wheels would not spin backwards. Anywho if I had ruined my fronts too I would have replaced the 4.11 and put 4.88 in. But being cheap I just redid the rear with 4.11s again. But to answer your question YES put lower gears (4.88) since you have to do the rear anyways. By the way are you running a V8?

 

[BigRed40]

By the way are you running a V8?

Yes I am. Small Block Chevy 350 putting out about 365 hp!

 

[BigRed40]

Would 5:29 be overkill?? Probably wouldn't be very streetable after that huh??

 

[Pin_Head]

5.29s with 38s would give you approximately the same final drive ratio (RPM/MPH) as the stock 4.11s with stock 29 inch tires.

 

[BigRed40]

5.29s with 38s would give you approximately the same final drive ratio (RPM/MPH) as the stock 4.11s with stock 29 inch tires.

Makes sense.. I appreciate the comments.. Thanks

 

[Copenhagen1]

5.29s with 38s would give you approximately the same final drive ratio (RPM/MPH) as the stock 4.11s with stock 29 inch tires.

Pin_Head , I have a question. I am not questioning your advice, just curious. If he had a 38" tires with the stock 2F I would see why you would go to 5.29s. The 5.29s would put him back in the torque band for that motor. Does he need the 5.29s with the 365 horse SBC?

I am asking because I still have the 2F. If I go with lower gears and bigger tires now and then later decide to put in a v8, I have been wondering if I would have to regear again.

Copenhagen1

 

[BigRed40]

Also, what company or brand would anyone suggest for 5:29's or 4.88's??

 

[inkpot]

Yes I am. Small Block Chevy 350 putting out about 365 hp!

Howdy! BTDT. Hare you got any kind of anti-wrap arm on the rear axle? If not, the your rear pinion is aimed at the sky when you hammer the throttle. You'll just keep breaking pinions. John

 

[Pin_Head]

Pin_Head , I have a question. I am not questioning your advice, just curious. If he had a 38" tires with the stock 2F I would see why you would go to 5.29s. The 5.29s would put him back in the torque band for that motor. Does he need the 5.29s with the 365 horse SBC?

That is a different question that I have no personal experience with. I would guess that a SBC would do better with the higher PRMs than a 2F that has optimal torque at lower RPMs.

 

[BigRed40]

Howdy! BTDT. Hare you got any kind of anti-wrap arm on the rear axle? If not, the your rear pinion is aimed at the sky when you hammer the throttle. You'll just keep breaking pinions. John

I don't have an anti-wrap bar on it now.. I normally would have just winched the guy out but since I didn't have my winch wired up that day (mistake), due to severe re-wiring lately, I had to try and tug him out. I never really peel out or cause too much wheel hop so it never has been a problem; plus, the flange bolts were very loose to an extent that it really didn't appear that the Pinion breaking was the cause of them being in that state. I'm just gunna use my winch from now on, play it safe, and not tug people out. Here's a pic of the Pinion

 

[Poser]

I don't have an anti-wrap bar on it now.. I normally would have just winched the guy out but since I didn't have my winch wired up that day (mistake), due to severe re-wiring lately, I had to try and tug him out. I never really peel out or cause too much wheel hop so it never has been a problem; plus, the flange bolts were very loose to an extent that it really didn't appear that the Pinion breaking was the cause of them being in that state. I'm just gunna use my winch from now on, play it safe, and not tug people out. Here's a pic of the Pinion

Well you can believe what you want, but that pinion failed because you are spring over, are not controlling the axle wrap and the drive shaft bound up at the pinion. Loose bolts on the drive shaft had very little to do with this failure.


If you continue to run your truck without a solid mechanical means of preventing the axle from rotating under load, you will destroy ANY Land Cruiser pinion you put into this application; fine or coarse spline.




Oh-

And as far as your 5.29 gear set question, I would not install them in anything other than a full float axle assembly, because of the amount of tooth material that would need to be removed in order to get the spider gear pinion shaft and c-clip thrust block into and out of the differential carrier.








Congrats on the broken junk.


Good luck!

 

[BigRed40]

Thanks for the input Poser. As far as the congratulations on the broken junk, I'm really not all that proud of it, I just was putting up a picture so the break could be seen. Initially something else came to mind when axle-wrap was mentioned earlier but now I understand what was meant. And I absolutely agree with the fact that something needs to be done to prevent the axle from rotating under load. I honestly haven't taken it out wheeling but twice in the last eight months because of work, college, and other business; and even then I tried not to push it too hard. Until this happened I guess I hadn't put too much thought into the axle-wrap issue with all the other kinks I've been trying to get worked out. Would 4:88 gears be ok with the semi-floater?? Thanks for the help.

 

[Poser]

Oh it is a process. Just be thankful that these Land Cruiser college credits are not costing you another 4.88 gear set....






4.88 gears are commonly installed into the Land Cruiser semi-float rear axle. You still need to modify a tooth on the ring gear in order to get the spider gear pinion shaft into the carrier, but you are not removing anywhere near the same amount of the ring gear tooth compared to the 5.29.


There are people who have installed the 5.29 gear set into the semi-float differentials, but I will not do it.





I was going to ask you how well the single reservoir/circuit drum brake system works for stopping 38.5s?

 

[BigRed40]

Oh it is a process. Just be thankful that these Land Cruiser college credits are not costing you another 4.88 gear set....

I was going to ask you how well the single reservoir/circuit drum brake system works for stopping 38.5s?

I am definitely very very thankful to everyone willing to give some good advice. As far as the drums go, I upgraded to stainless steel lines which helped a little by adding some pressure to the lines but it still takes a good full pump of the brake pedal to put some real pressure in the lines and then another pump will stop the tires pretty well. That stock single reservoir master cylinder really isn't enough for those tires though. I just bought a much larger dual reservoir master cylinder and hopefully I can get to disc brakes at some point. I just wish I had more time and money dang it

 

[Pin_Head]

it still takes a good full pump of the brake pedal to put some real pressure in the lines and then another pump will stop the tires pretty well.

That is the classic sign that your brakes need adjusting. Don't put it off because you may be in a situation where you don't have time to double pump.

 

[MarcoPolo]

That is the classic sign that your brakes need adjusting. Don't put it off because you may be in a situation where you don't have time to double pump.

Been there.. done that.. Paid enough along the way to end the insanity..

Just be thankful that these Land Cruiser college credits are not costing you another 4.88 gear set....

Wisdom of Poser..........................................Priceless

 

[BigRed40]

That is the classic sign that your brakes need adjusting. Don't put it off because you may be in a situation where you don't have time to double pump.

Yeah, I definitely agree with you on that one. New master cylinder and disc brakes are at the top of the list as far as projects are concerned. I have a daily driver that gets 35 mpg so I drive it everywhere and very rarely do I get to drive around my 40 cause I always have her taken apart working on another project When I do though, I drive very carefully and keep my distance from other vehicles!

 

[Pin_Head]

It is a 15 minute job, so don't roll the dice.

 

[BigRed40]

I appreciate the concern... I was at least gunna put on that new master cylinder while I was waiting to get the new gears.. I just need to machine up a small adapter plate before it will fit and then it'll be on there and ready to go.