Final Drive Gear Ratios

**Ungas** · July 17th, 2003 08:56 PM

Di ba ang 5th gear is supposed to be an overdrive gear? I used to do 140-150km/h on 5th gear without any problems on my 32" A/T tires. But since I opted for a slightly larger 33" M/T tires, I find it difficult for the 5th gear to maintain running speed around 120km/h, inshort, bumababa ang speed ko to about 100km/h. Madalas ko na lang gamitin 4th gear and pedal to the metal when I want it to reach above 120km/h. Then shift to 5th gear so that it won't be too harsh for the engine.

**ARB** · July 17th, 2003 10:33 PM

in that case you need to re gear. he he additional cost nanaman. but most pickups have 4.56 ratio, and still can maintain the speed you mentioned. baka iba rear diff ratio mo. 4.11 maybe.

**Bubbles** · July 18th, 2003 12:18 AM

ARB, Si bubbles, naka 38. It still accelerates fine. top speed 90. Japan version. Pero kinabit namin 38 sa local patrol, bad acceleration na. With only 2 available ratios, malamang ako naka 4.56 local naka 3.75. Sa acceleration kasi kaya ko ang stock patrol until 3rd gear. considering my body is around 1.5x as heavy as the stock. either finaldrive nagkaiba or transmission.

**johnqpublic318** · July 18th, 2003 09:12 AM

My spec sheet for the 96 4.2L naturally aspirated Nissan Patrol Safari with the rear locker said 4.555 to be more exact. I was working for Volvo back then and UMC was our sister company. If someone wants to dispute this then that's their prerogative. How about we bet money on it? I'm not saying I'm right but I'm willing to lose P1,000 over it. Remember, this is for the Phil spec 94-99 Nissan Patrol Safari equipped with the TD42 and 5-speed manual transmission.

Ungas,

Your speedo reading is calibrated for your stock tires and gearing... Stock Phil spec Patrol Safaris were equipped with 31-10.5-15 tires and if you're now running 33s then your speedo will read 6.5% slow... This means at 100kph, you're actually travelling 106.5.... At 120kph, your actual speed is around 127.8kph...

If you have 32s then the error will be just 3.23%...

Retaining stock gearing and adding larger tires will make your speedo show a lower speed than what you're running...

Of course there could be a number of factors that can affect top-speed or speedo readings such as road conditions, climate, vehicle condition or actual speedo error itself...

**Ungas** · July 18th, 2003 09:32 AM

ARB::: That's what I'm afraid of, additional costs that shouldn't be there in the first place. :whoa:

johnqpublic318::: My theories are only based on Aussie's technical forums. Diff gears or transaxle gears are stamped on body and plate panels located under the hood. To be frank about it, at first I don't have any rough idea on what is the Patrol's gearing really is. Confused? I have compared the speeds at the same point in Tabang exit along NLEX. Hmmm... this could be an interesting trivial pursuit, a friendly challenge. My bet is on a lower value between 3.375 to at the most 4.11. Let's both be present at the actual count. :D

Uhhmm, one more thing, could we count it by not getting messy and dismantling the gears? Rather counting it by how many axle and propeller turns. :D

**Bubbles** · July 18th, 2003 11:03 AM

johnqpublic318,

Meron bang different tranny gears?

Right now at 60 I'm running 10kph faster then the speedo. My speedo says 50. I know dapat in percent diba. wat i do nalang is add 10 kph. ok ba yun?

**johnqpublic318** · July 18th, 2003 03:51 PM

Ungas,

Sure, you don't have to dismantle anything and you can just get a close estimate by using chalk and counting the number of times your driveshaft rotates versus one tire rotation. Check twice, average and compare with available axle ratios for the GQ Patrol Suv equipped with a manual and TD42. If you get a count of 4.5 then you have a 4.555/56 axle gearset.

Yes, you are right by saying that there are different axle ratios available for the GQ Patrol.

**johnqpublic318** · July 18th, 2003 04:00 PM

Originally posted by Bubbles
johnqpublic318,

Meron bang different tranny gears?

Right now at 60 I'm running 10kph faster then the speedo. My speedo says 50. I know dapat in percent diba. wat i do nalang is add 10 kph. ok ba yun?

I'm not sure about aftermarket tranny gears but what you really need to change is your axle gears to correct for speedo error.

For instance if your stock gearing is 4.56 and you changed tires from 31s to 33s then a move to 4.88 gears will lessen your speedo error. However, going from 31s to 33s may not merit the inconvenience and cost of re-gearing. This is your call.

Axles gearsets and lower t-case (not tranny) gears for the GQ Patrol are available in Australia from: http://www.bigballsoffroad.com . This is an excellent site for Japanese 4x4 owners.

Good luck.

**Bubbles** · July 18th, 2003 04:56 PM

Actually, I meant kung meron ba na different set of tranny gears from the factory. I'm comfy na with my speedo and the car drives ok on the 38's. This confusion kasi on the final drive. May factory gears pa ba taller than 4.56?