gearbox and diff ratios...

[sparkz]

Hi All...

i recently transplanted a 2,4TD engine and manual box in to my Hilux pickup...at the same time i fitted some 35" BFG muds

the only problem i have is ratios!...im running the standard pickup axles...the 2.4TD gearbox from a 91 surf and a 2L-TE engine...

i know ideally i should be looking to change diff ratios to suit the new wheels..

but if it improves matters...im thinkin of putting my pickup gearbox back on to help out in the mean time..the original engine and box was a standard 2.4D egine and box..

i have some information regarding gearbox ratios on various gearbox model numbers, however im not sure which boxes i have!...

any information/advice would be greatfully recieved

[Gamedawn]

I wouldn't have thought that changing the gearbox is going to make that much difference. Generally top gear is much the same from one box to another. Really you ought to be changing the diffs and I would have guessed that to make 35's turn it a satisfactory manner you probably want 5.1:1 or certainly high 4.something as a ratio.

[stormforce]

i would of thought you would need to regear.TheLovelyBoyo fitted 33's on his 2.4 and noticed a loss of power with them on so you will get a lot more loss of power i would of thought with 35's

[sparkz]

I wouldn't have thought that changing the gearbox is going to make that much difference. Generally top gear is much the same from one box to another. Really you ought to be changing the diffs and I would have guessed that to make 35's turn it a satisfactory manner you probably want 5.1:1 or certainly high 4.something as a ratio.

top gear is a distant dream... main problem is changing from 3rd to 4th..there seems to be a big jump between those gears..5th i can get down hill...and assuming the wind is in the right direction i can just about hold speed on the flat..but most of the time...im not leaving 3rd!...

still not ruled out having engine isues..but just wanna figure out if there is any difference in ratios between the 2 boxes that could be adding to the problem...assuming they are the same (ish) i can always put my old wheels back on and see how it drives then...

i guess in hindsight...i should have done one job at a time!

[The Lovely Boyo]

This page

http://toyota.off-road.com/toyota/ar....jsp?id=274535

although American, has some useful info about how to identify what you got

[NiftyNev]

If you work out what gearboxes you have then all the ratio info is here.

http://en.wikipedia.org/wiki/Toyota_transmissions

I say leave the gearbox and change diffs.

Nev

[sparkz]

Cheers guys...

wow..would never thought of trying wikipedia for ratios!...

im still not convined the slugishness is solely due to wheels tho..so i might put the old wheels back on..and see how it performs

Thanks again for all your help

S

[The Lovely Boyo]

im still not convined the slugishness is solely due to wheels tho..so i might put the old wheels back on..and see how it performs

As Richard said, I have noticable loss of performance when I got my mud tyres on. Put them on this Saturday for yesterdays off roading. My 31's will be back on today.

My road tyres are standard 31 10.5's. My muds are 33 12.5's.

The muds are excellent off road. On road I have poor acceleration, noisy, higher fuel consumption and struggles to maintain momentum when at speed.

Part of this will be caused by their weight - I can handle the 31's no problem - I struggle to even lift the 33's. Combined with the aggresive tread and larger width and diameter, rolling resistance will be much higher.

Until I get my diffs regeared I will keep swapping them over.

[sparkz]

As Richard said, I have noticable loss of performance when I got my mud tyres on. Put them on this Saturday for yesterdays off roading. My 31's will be back on today.

My road tyres are standard 31 10.5's. My muds are 33 12.5's.

The muds are excellent off road. On road I have poor acceleration, noisy, higher fuel consumption and struggles to maintain momentum when at speed.

Part of this will be caused by their weight - I can handle the 31's no problem - I struggle to even lift the 33's. Combined with the aggresive tread and larger width and diameter, rolling resistance will be much higher.

Until I get my diffs regeared I will keep swapping them over.

ok..thats reasuring in a way...ill deff put my old wheels back on and see how it drives to confirm...

next question...a pair of diffs...how much is this gonna set me back

[TonyN]

ok..thats reasuring in a way...ill deff put my old wheels back on and see how it drives to confirm...

next question...a pair of diffs...how much is this gonna set me back

I sold my used diffs for £80 each (8" rears, and pickup fronts, not 7 1/2" fronts you find on Surfs) To regear from new is about £180 or so for the gears, and £200ish for fitting kit and install, for each end, so not much change from £800 for both ends.

[The Lovely Boyo]

I sold my used diffs for £80 each (8" rears, and pickup fronts, not 7 1/2" fronts you find on Surfs) To regear from new is about £180 or so for the gears, and £200ish for fitting kit and install, for each end, so not much change from £800 for both ends.

Holy Bank Balance, Batman!

I was gonna throw a locker in as well when I changed mine - looks like I better go and sell a kidney.

Tony - have you got your ARB installed yet? If so, how is it?

I was thinking of going to something like a PosiLok or similar - mild off roading, not really extreme stuff.

[sparkz]

I sold my used diffs for £80 each (8" rears, and pickup fronts, not 7 1/2" fronts you find on Surfs) To regear from new is about £180 or so for the gears, and £200ish for fitting kit and install, for each end, so not much change from £800 for both ends.

<faints>

i guess i can save on the labour side..i have a mate whos a master technican..so will be callin in a favor me thinks...

just gotta get me hands on a nice second hand pair...£80 a set i can live with..

i dont suppose to size im after is common to anything else?..sorta broaden the serching horizon so to speak!

thanks again Tony..


S

[TonyN]

Surfs come with 4.1's or 4.3, even 4.5's, We got 4.8's to replace the 4.1's in Linda's truck for her 33" tyres. Your trouble is most of the pickup diff's I've seen have been 4.88 already, taller than that is in the 5.x range, with you don't see from the factory.

You need to find out what you have.

<faints>

i guess i can save on the labour side..i have a mate whos a master technican..so will be callin in a favor me thinks...

just gotta get me hands on a nice second hand pair...£80 a set i can live with..

i dont suppose to size im after is common to anything else?..sorta broaden the serching horizon so to speak!

thanks again Tony..


S

[The Lovely Boyo]

Surfs come with 4.1's or 4.3, even 4.5's, We got 4.8's to replace the 4.1's in Linda's truck for her 33" tyres. Your trouble is most of the pickup diff's I've seen have been 4.88 already, taller than that is in the 5.x range, with you don't see from the factory.

You need to find out what you have.

I was thinking of 4.88's for mine.

This site had the 5.xx gears

http://www.4wheelparts.com/4wp/produ...NU&expand=sub9

However - I have read somewhere that as they cut additional teeth to lower the ratio they start to weaken (not much metal left!).

[sparkz]

Surfs come with 4.1's or 4.3, even 4.5's, We got 4.8's to replace the 4.1's in Linda's truck for her 33" tyres. Your trouble is most of the pickup diff's I've seen have been 4.88 already, taller than that is in the 5.x range, with you don't see from the factory.

You need to find out what you have.

im assuming mine is stock...so will find out what i have..then from there..figure out where i gotta go to...

i might have a pair of 4.88's up for sale soon Boyo

Cheers Tony